a bug fix...
[IRC.git] / Robust / src / Analysis / SSJava / LocationInference.java
index 089e7f8bd7f887d07989135c48ce35a08eda8515..b15742f55874221a52703f4ddf5653a6cb7b39fa 100644 (file)
@@ -1,5 +1,9 @@
 package Analysis.SSJava;
 
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.FileReader;
+import java.io.FileWriter;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -12,9 +16,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.Stack;
+import java.util.Vector;
 
-import Analysis.SSJava.FlowDownCheck.ComparisonResult;
-import Analysis.SSJava.FlowDownCheck.CompositeLattice;
 import IR.ClassDescriptor;
 import IR.Descriptor;
 import IR.FieldDescriptor;
@@ -24,6 +27,7 @@ import IR.Operation;
 import IR.State;
 import IR.SymbolTable;
 import IR.TypeDescriptor;
+import IR.TypeUtil;
 import IR.VarDescriptor;
 import IR.Tree.ArrayAccessNode;
 import IR.Tree.AssignmentNode;
@@ -44,77 +48,235 @@ import IR.Tree.NameNode;
 import IR.Tree.OpNode;
 import IR.Tree.ReturnNode;
 import IR.Tree.SubBlockNode;
+import IR.Tree.SwitchBlockNode;
 import IR.Tree.SwitchStatementNode;
 import IR.Tree.TertiaryNode;
+import IR.Tree.TreeNode;
+import Util.Pair;
 
 public class LocationInference {
 
+  static int COUNT = 0;
+
   State state;
   SSJavaAnalysis ssjava;
+  TypeUtil tu;
 
-  List<ClassDescriptor> toanalyzeList;
-  List<MethodDescriptor> toanalyzeMethodList;
+  List<ClassDescriptor> temp_toanalyzeList;
+  List<MethodDescriptor> temp_toanalyzeMethodList;
   Map<MethodDescriptor, FlowGraph> mapMethodDescriptorToFlowGraph;
 
+  LinkedList<MethodDescriptor> toanalyze_methodDescList;
+  Set<ClassDescriptor> toanalyze_classDescSet;
+
+  // InheritanceTree<ClassDescriptor> inheritanceTree;
+
   // map a method descriptor to its set of parameter descriptors
   Map<MethodDescriptor, Set<Descriptor>> mapMethodDescriptorToParamDescSet;
 
   // keep current descriptors to visit in fixed-point interprocedural analysis,
   private Stack<MethodDescriptor> methodDescriptorsToVisitStack;
 
+  // map a descriptor to a naive lattice
+  private Map<Descriptor, SSJavaLattice<String>> desc2naiveLattice;
+
   // map a class descriptor to a field lattice
   private Map<ClassDescriptor, SSJavaLattice<String>> cd2lattice;
 
   // map a method descriptor to a method lattice
   private Map<MethodDescriptor, SSJavaLattice<String>> md2lattice;
 
+  // map a method/class descriptor to a hierarchy graph
+  private Map<Descriptor, HierarchyGraph> mapDescriptorToHierarchyGraph;
+
+  // map a method/class descriptor to a skeleton hierarchy graph
+  private Map<Descriptor, HierarchyGraph> mapDescriptorToSkeletonHierarchyGraph;
+
+  private Map<Descriptor, HierarchyGraph> mapDescriptorToSimpleHierarchyGraph;
+
+  // map a method/class descriptor to a skeleton hierarchy graph with combination nodes
+  private Map<Descriptor, HierarchyGraph> mapDescriptorToCombineSkeletonHierarchyGraph;
+
+  // map a descriptor to a simple lattice
+  private Map<Descriptor, SSJavaLattice<String>> mapDescriptorToSimpleLattice;
+
   // map a method descriptor to the set of method invocation nodes which are
   // invoked by the method descriptor
   private Map<MethodDescriptor, Set<MethodInvokeNode>> mapMethodDescriptorToMethodInvokeNodeSet;
 
   private Map<MethodInvokeNode, Map<Integer, NTuple<Descriptor>>> mapMethodInvokeNodeToArgIdxMap;
 
-  private Map<MethodDescriptor, MethodLocationInfo> mapLatticeToMethodLocationInfo;
+  private Map<MethodInvokeNode, NTuple<Descriptor>> mapMethodInvokeNodeToBaseTuple;
+
+  private Map<MethodInvokeNode, Set<NTuple<Location>>> mapMethodInvokeNodeToPCLocTupleSet;
+
+  private Map<MethodDescriptor, MethodLocationInfo> mapMethodDescToMethodLocationInfo;
+
+  private Map<ClassDescriptor, LocationInfo> mapClassToLocationInfo;
+
+  private Map<MethodDescriptor, Set<MethodDescriptor>> mapMethodToCalleeSet;
+
+  private Map<MethodDescriptor, Set<FlowNode>> mapMethodDescToParamNodeFlowsToReturnValue;
+
+  private Map<String, Vector<String>> mapFileNameToLineVector;
+
+  private Map<Descriptor, Integer> mapDescToDefinitionLine;
+
+  private Map<Descriptor, LocationSummary> mapDescToLocationSummary;
+
+  private Map<MethodDescriptor, Set<MethodInvokeNode>> mapMethodDescToMethodInvokeNodeSet;
+
+  // maps a method descriptor to a sub global flow graph that captures all value flows caused by the
+  // set of callees reachable from the method
+  private Map<MethodDescriptor, GlobalFlowGraph> mapMethodDescriptorToSubGlobalFlowGraph;
+
+  private Map<MethodInvokeNode, Map<NTuple<Descriptor>, NTuple<Descriptor>>> mapMethodInvokeNodeToMapCallerArgToCalleeArg;
+
+  private Map<MethodDescriptor, Boolean> mapMethodDescriptorToCompositeReturnCase;
+
+  private Map<MethodDescriptor, MethodDescriptor> mapMethodDescToHighestOverriddenMethodDesc;
+
+  private Map<MethodDescriptor, Set<MethodDescriptor>> mapHighestOverriddenMethodDescToMethodDescSet;
+
+  private Map<MethodDescriptor, NTuple<Descriptor>> mapHighestOverriddenMethodDescToReturnLocTuple;
+
+  private Map<MethodDescriptor, NTuple<Descriptor>> mapHighestOverriddenMethodDescToPCLocTuple;
+
+  private Map<MethodDescriptor, Set<NTuple<Descriptor>>> mapHighestOverriddenMethodDescToSetLowerThanPCLoc;
+
+  private Map<MethodDescriptor, Set<NTuple<Descriptor>>> mapHighestOverriddenMethodDescToSetHigherThanRETURNLoc;
+
+  public static final String GLOBALLOC = "GLOBALLOC";
+
+  public static final String INTERLOC = "INTERLOC";
+
+  public static final String PCLOC = "_PCLOC_";
+
+  public static final String RLOC = "_RLOC_";
+
+  public static final Descriptor GLOBALDESC = new NameDescriptor(GLOBALLOC);
 
-  private Map<MethodDescriptor, Set<MethodDescriptor>> mapMethodDescToPossibleMethodDescSet;
+  public static final Descriptor TOPDESC = new NameDescriptor(SSJavaAnalysis.TOP);
+
+  public static final Descriptor BOTTOMDESC = new NameDescriptor(SSJavaAnalysis.BOTTOM);
+
+  public static final Descriptor RETURNLOC = new NameDescriptor(RLOC);
+
+  public static final Descriptor LITERALDESC = new NameDescriptor("LITERAL");
+
+  public static final HNode TOPHNODE = new HNode(TOPDESC);
+
+  public static final HNode BOTTOMHNODE = new HNode(BOTTOMDESC);
+
+  public static String newline = System.getProperty("line.separator");
+
+  LocationInfo curMethodInfo;
+
+  private boolean hasChanges = false;
 
   boolean debug = true;
 
-  public LocationInference(SSJavaAnalysis ssjava, State state) {
+  public static int locSeed = 0;
+
+  private Stack<String> arrayAccessNodeStack;
+
+  private ClassDescriptor rootClassDescriptor;
+
+  private BuildLattice buildLattice;
+
+  public static int numLocationsSInfer = 0;
+  public static int numLocationsNaive = 0;
+
+  public LocationInference(SSJavaAnalysis ssjava, State state, TypeUtil tu) {
     this.ssjava = ssjava;
     this.state = state;
-    this.toanalyzeList = new ArrayList<ClassDescriptor>();
-    this.toanalyzeMethodList = new ArrayList<MethodDescriptor>();
+    this.tu = tu;
+    this.toanalyze_classDescSet = new HashSet<ClassDescriptor>();
+    this.temp_toanalyzeList = new ArrayList<ClassDescriptor>();
+    this.temp_toanalyzeMethodList = new ArrayList<MethodDescriptor>();
     this.mapMethodDescriptorToFlowGraph = new HashMap<MethodDescriptor, FlowGraph>();
     this.cd2lattice = new HashMap<ClassDescriptor, SSJavaLattice<String>>();
     this.md2lattice = new HashMap<MethodDescriptor, SSJavaLattice<String>>();
+    this.desc2naiveLattice = new HashMap<Descriptor, SSJavaLattice<String>>();
+
     this.methodDescriptorsToVisitStack = new Stack<MethodDescriptor>();
     this.mapMethodDescriptorToMethodInvokeNodeSet =
         new HashMap<MethodDescriptor, Set<MethodInvokeNode>>();
     this.mapMethodInvokeNodeToArgIdxMap =
         new HashMap<MethodInvokeNode, Map<Integer, NTuple<Descriptor>>>();
-    this.mapLatticeToMethodLocationInfo = new HashMap<MethodDescriptor, MethodLocationInfo>();
-    this.mapMethodDescToPossibleMethodDescSet =
+    this.mapMethodDescToMethodLocationInfo = new HashMap<MethodDescriptor, MethodLocationInfo>();
+    this.mapMethodToCalleeSet = new HashMap<MethodDescriptor, Set<MethodDescriptor>>();
+    this.mapClassToLocationInfo = new HashMap<ClassDescriptor, LocationInfo>();
+
+    this.mapFileNameToLineVector = new HashMap<String, Vector<String>>();
+    this.mapDescToDefinitionLine = new HashMap<Descriptor, Integer>();
+    this.mapMethodDescToParamNodeFlowsToReturnValue =
+        new HashMap<MethodDescriptor, Set<FlowNode>>();
+
+    this.mapDescriptorToHierarchyGraph = new HashMap<Descriptor, HierarchyGraph>();
+    this.mapMethodInvokeNodeToBaseTuple = new HashMap<MethodInvokeNode, NTuple<Descriptor>>();
+
+    this.mapDescriptorToSkeletonHierarchyGraph = new HashMap<Descriptor, HierarchyGraph>();
+    this.mapDescriptorToCombineSkeletonHierarchyGraph = new HashMap<Descriptor, HierarchyGraph>();
+    this.mapDescriptorToSimpleHierarchyGraph = new HashMap<Descriptor, HierarchyGraph>();
+
+    this.mapDescriptorToSimpleLattice = new HashMap<Descriptor, SSJavaLattice<String>>();
+
+    this.mapDescToLocationSummary = new HashMap<Descriptor, LocationSummary>();
+
+    this.mapMethodDescriptorToSubGlobalFlowGraph = new HashMap<MethodDescriptor, GlobalFlowGraph>();
+
+    this.mapMethodInvokeNodeToMapCallerArgToCalleeArg =
+        new HashMap<MethodInvokeNode, Map<NTuple<Descriptor>, NTuple<Descriptor>>>();
+
+    this.mapMethodInvokeNodeToPCLocTupleSet =
+        new HashMap<MethodInvokeNode, Set<NTuple<Location>>>();
+
+    this.arrayAccessNodeStack = new Stack<String>();
+
+    this.mapMethodDescToMethodInvokeNodeSet =
+        new HashMap<MethodDescriptor, Set<MethodInvokeNode>>();
+
+    this.mapMethodDescriptorToCompositeReturnCase = new HashMap<MethodDescriptor, Boolean>();
+
+    mapMethodDescToHighestOverriddenMethodDesc = new HashMap<MethodDescriptor, MethodDescriptor>();
+
+    mapHighestOverriddenMethodDescToSetLowerThanPCLoc =
+        new HashMap<MethodDescriptor, Set<NTuple<Descriptor>>>();
+
+    mapHighestOverriddenMethodDescToMethodDescSet =
         new HashMap<MethodDescriptor, Set<MethodDescriptor>>();
+
+    mapHighestOverriddenMethodDescToReturnLocTuple =
+        new HashMap<MethodDescriptor, NTuple<Descriptor>>();
+
+    mapHighestOverriddenMethodDescToPCLocTuple =
+        new HashMap<MethodDescriptor, NTuple<Descriptor>>();
+
+    mapHighestOverriddenMethodDescToSetHigherThanRETURNLoc =
+        new HashMap<MethodDescriptor, Set<NTuple<Descriptor>>>();
+
+    this.buildLattice = new BuildLattice(this);
+
   }
 
   public void setupToAnalyze() {
     SymbolTable classtable = state.getClassSymbolTable();
-    toanalyzeList.clear();
-    toanalyzeList.addAll(classtable.getValueSet());
-    Collections.sort(toanalyzeList, new Comparator<ClassDescriptor>() {
-      public int compare(ClassDescriptor o1, ClassDescriptor o2) {
-        return o1.getClassName().compareToIgnoreCase(o2.getClassName());
-      }
-    });
+    temp_toanalyzeList.clear();
+    temp_toanalyzeList.addAll(classtable.getValueSet());
+    // Collections.sort(toanalyzeList, new Comparator<ClassDescriptor>() {
+    // public int compare(ClassDescriptor o1, ClassDescriptor o2) {
+    // return o1.getClassName().compareToIgnoreCase(o2.getClassName());
+    // }
+    // });
   }
 
   public void setupToAnalazeMethod(ClassDescriptor cd) {
 
     SymbolTable methodtable = cd.getMethodTable();
-    toanalyzeMethodList.clear();
-    toanalyzeMethodList.addAll(methodtable.getValueSet());
-    Collections.sort(toanalyzeMethodList, new Comparator<MethodDescriptor>() {
+    temp_toanalyzeMethodList.clear();
+    temp_toanalyzeMethodList.addAll(methodtable.getValueSet());
+    Collections.sort(temp_toanalyzeMethodList, new Comparator<MethodDescriptor>() {
       public int compare(MethodDescriptor o1, MethodDescriptor o2) {
         return o1.getSymbol().compareToIgnoreCase(o2.getSymbol());
       }
@@ -122,390 +284,4521 @@ public class LocationInference {
   }
 
   public boolean toAnalyzeMethodIsEmpty() {
-    return toanalyzeMethodList.isEmpty();
+    return temp_toanalyzeMethodList.isEmpty();
   }
 
   public boolean toAnalyzeIsEmpty() {
-    return toanalyzeList.isEmpty();
+    return temp_toanalyzeList.isEmpty();
   }
 
   public ClassDescriptor toAnalyzeNext() {
-    return toanalyzeList.remove(0);
+    return temp_toanalyzeList.remove(0);
   }
 
   public MethodDescriptor toAnalyzeMethodNext() {
-    return toanalyzeMethodList.remove(0);
+    return temp_toanalyzeMethodList.remove(0);
   }
 
   public void inference() {
 
-    // 1) construct value flow graph
+    ssjava.init();
+
+    // construct value flow graph
     constructFlowGraph();
 
-    // 2) construct lattices
-    inferLattices();
+    constructGlobalFlowGraph();
 
-    debug_writeLatticeDotFile();
+    checkReturnNodes();
 
-    // 3) check properties
-    checkLattices();
+    assignCompositeLocation();
+    updateFlowGraph();
+    calculateExtraLocations();
+    addAdditionalOrderingConstraints();
 
-  }
+    _debug_writeFlowGraph();
 
-  private void checkLattices() {
+    buildInheritanceTree();
+    calculateReturnPCLocInheritance();
 
-    LinkedList<MethodDescriptor> descriptorListToAnalyze = ssjava.getSortedDescriptors();
+    constructHierarchyGraph();
 
-    // current descriptors to visit in fixed-point interprocedural analysis,
-    // prioritized by
-    // dependency in the call graph
-    methodDescriptorsToVisitStack.clear();
+    addInheritanceConstraintsToHierarchyGraph();
 
-    descriptorListToAnalyze.removeFirst();
+    debug_writeHierarchyDotFiles();
 
-    Set<MethodDescriptor> methodDescriptorToVistSet = new HashSet<MethodDescriptor>();
-    methodDescriptorToVistSet.addAll(descriptorListToAnalyze);
+    simplifyHierarchyGraph();
 
-    while (!descriptorListToAnalyze.isEmpty()) {
-      MethodDescriptor md = descriptorListToAnalyze.removeFirst();
-      checkLatticesOfVirtualMethods(md);
+    debug_writeSimpleHierarchyDotFiles();
+
+    constructSkeletonHierarchyGraph();
+
+    debug_writeSkeletonHierarchyDotFiles();
+
+    insertCombinationNodes();
+
+    debug_writeSkeletonCombinationHierarchyDotFiles();
+
+    buildLatticeInheritanceTree();
+    // buildLattice();
+
+    debug_writeLattices();
+
+    updateCompositeLocationAssignments();
+
+    generateMethodSummary();
+
+    generateAnnoatedCode();
+
+    for (Iterator iterator = cd2lattice.keySet().iterator(); iterator.hasNext();) {
+      ClassDescriptor cd = (ClassDescriptor) iterator.next();
+      SSJavaLattice<String> lattice = getLattice(cd);
+      HierarchyGraph hg = mapDescriptorToHierarchyGraph.get(cd);
+      // System.out.println("~~~\t" + cd + "\t" + lattice.getKeySet().size() + "\t"
+      // + hg.getNodeSet().size());
     }
 
-  }
+    for (Iterator iterator = md2lattice.keySet().iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      SSJavaLattice<String> locOrder = getLattice(md);
+      // writeLatticeDotFile(md.getClassDesc(), md, getMethodLattice(md));
+      HierarchyGraph hg = mapDescriptorToHierarchyGraph.get(md);
+      // System.out.println("~~~\t" + md.getClassDesc() + "_" + md + "\t"
+      // + locOrder.getKeySet().size() + "\t" + hg.getNodeSet().size());
+    }
 
-  private void debug_writeLatticeDotFile() {
-    // generate lattice dot file
+    if (state.SSJAVA_INFER_NAIVE_WRITEDOTS) {
+      System.out.println("The number of elements: Naive=" + numLocationsNaive);
+    }
+    System.out.println("The number of elements: SInfer=" + numLocationsSInfer);
 
-    setupToAnalyze();
+    System.exit(0);
 
-    while (!toAnalyzeIsEmpty()) {
-      ClassDescriptor cd = toAnalyzeNext();
+  }
 
-      setupToAnalazeMethod(cd);
+  private void calculateReturnPCLocInheritance() {
+    calculateHighestPCLocInheritance();
+    calculateLowestReturnLocInheritance();
+    updateFlowGraphPCReturnLocInheritance();
+  }
 
-      SSJavaLattice<String> classLattice = cd2lattice.get(cd);
-      if (classLattice != null) {
-        ssjava.writeLatticeDotFile(cd, null, classLattice);
+  private void updateFlowGraphPCReturnLocInheritance() {
+
+    Set<MethodDescriptor> keySet = mapHighestOverriddenMethodDescToMethodDescSet.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      MethodDescriptor highestMethodDesc = (MethodDescriptor) iterator.next();
+
+      if (mapHighestOverriddenMethodDescToMethodDescSet.get(highestMethodDesc).size() == 1) {
+        continue;
       }
 
-      while (!toAnalyzeMethodIsEmpty()) {
-        MethodDescriptor md = toAnalyzeMethodNext();
-        if (ssjava.needTobeAnnotated(md)) {
-          SSJavaLattice<String> methodLattice = md2lattice.get(md);
-          if (methodLattice != null) {
-            ssjava.writeLatticeDotFile(cd, md, methodLattice);
+      Set<MethodDescriptor> methodDescSet =
+          mapHighestOverriddenMethodDescToMethodDescSet.get(highestMethodDesc);
+
+      NTuple<Descriptor> highestPCLocDescTuple =
+          mapHighestOverriddenMethodDescToPCLocTuple.get(highestMethodDesc);
+
+      NTuple<Descriptor> highestRETURNLocDescTuple =
+          mapHighestOverriddenMethodDescToReturnLocTuple.get(highestMethodDesc);
+
+      // System.out.println("\n$$$$$$$$$$$$$$$$updateFlowGraphPCReturnLocInheritance="
+      // + highestMethodDesc);
+      // System.out.println("-----highestPCLoc=" + highestPCLocDescTuple);
+      // System.out.println("-----highestRETURNLoc=" + highestRETURNLocDescTuple);
+
+      for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+        MethodDescriptor md = (MethodDescriptor) iterator2.next();
+        // System.out.println("\n --------MD=" + md);
+        FlowGraph flowGraph = getFlowGraph(md);
+
+        MethodSummary summary = getMethodSummary(md);
+        CompositeLocation curPCLoc = summary.getPCLoc();
+        NTuple<Descriptor> curPCDescTuple = translateToDescTuple(curPCLoc.getTuple());
+        // System.out.println("md=" + md + "  curPCLoc=" + curPCLoc);
+        // System.out.println("highestPCLoc=" + highestPCLocDescTuple);
+
+        if (highestPCLocDescTuple == null) {
+          // this case: PCLOC is top
+          // System.out.println("###SET PCLOC AS TOP");
+          if (curPCDescTuple != null && !curPCLoc.get(0).isTop()) {
+            FlowNode pcFlowNode = flowGraph.getFlowNode(curPCDescTuple);
+            flowGraph.removeNode(pcFlowNode);
+          }
+          summary.setPCLoc(new CompositeLocation(new Location(md, Location.TOP)));
+        } else {
+          NTuple<Descriptor> newPCDescTuple = new NTuple<Descriptor>();
+          if (highestPCLocDescTuple.size() == 1) {
+            newPCDescTuple.add(highestPCLocDescTuple.get(0));
+          } else {
+            newPCDescTuple.add(md.getThis());
+            newPCDescTuple.add(highestPCLocDescTuple.get(1));
+          }
+          if (!curPCDescTuple.equals(newPCDescTuple)) {
+            FlowNode pcFlowNode = flowGraph.getFlowNode(curPCDescTuple);
+            flowGraph.updateTuple(pcFlowNode, newPCDescTuple);
+            // flowGraph.removeNode(pcFlowNode);
+            Set<NTuple<Descriptor>> descSetLowerThanPCLoc =
+                mapHighestOverriddenMethodDescToSetLowerThanPCLoc.get(highestMethodDesc);
+            for (Iterator iterator3 = descSetLowerThanPCLoc.iterator(); iterator3.hasNext();) {
+              NTuple<Descriptor> lowerNTuple = (NTuple<Descriptor>) iterator3.next();
+              flowGraph.addValueFlowEdge(newPCDescTuple, lowerNTuple);
+            }
+            CompositeLocation newPCCompLoc =
+                new CompositeLocation(translateToLocTuple(md, newPCDescTuple));
+            summary.setPCLoc(newPCCompLoc);
+          }
+
+        }
+
+        // update return loc
+        if (highestRETURNLocDescTuple != null) {
+          CompositeLocation curRETURNLoc = summary.getRETURNLoc();
+          NTuple<Descriptor> curReturnDescTuple = translateToDescTuple(curRETURNLoc.getTuple());
+
+          if (!curReturnDescTuple.equals(highestRETURNLocDescTuple)) {
+            // handle the case that RETURNLOC is started with 'this'...
+            NTuple<Descriptor> newRETURNLocDescTuple = new NTuple<Descriptor>();
+            if (highestRETURNLocDescTuple.size() == 1) {
+              newRETURNLocDescTuple.add(highestRETURNLocDescTuple.get(0));
+            } else {
+              newRETURNLocDescTuple.add(md.getThis());
+              newRETURNLocDescTuple.add(highestRETURNLocDescTuple.get(1));
+            }
+
+            FlowNode returnFlowNode = flowGraph.getFlowNode(curReturnDescTuple);
+            flowGraph.updateTuple(returnFlowNode, newRETURNLocDescTuple);
+
+            Set<NTuple<Descriptor>> descSetHigherThanRETURNLoc =
+                mapHighestOverriddenMethodDescToSetHigherThanRETURNLoc.get(highestMethodDesc);
+            for (Iterator iterator3 = descSetHigherThanRETURNLoc.iterator(); iterator3.hasNext();) {
+              NTuple<Descriptor> higherNTuple = (NTuple<Descriptor>) iterator3.next();
+              flowGraph.addValueFlowEdge(higherNTuple, newRETURNLocDescTuple);
+            }
+
+            CompositeLocation newRETURNLocCompLoc =
+                new CompositeLocation(translateToLocTuple(md, newRETURNLocDescTuple));
+            summary.setRETURNLoc(newRETURNLocCompLoc);
           }
         }
       }
     }
-
   }
 
-  private void inferLattices() {
+  private void calculateHighestPCLocInheritance() {
 
-    // do fixed-point analysis
+    Set<MethodDescriptor> keySet = mapHighestOverriddenMethodDescToMethodDescSet.keySet();
 
-    LinkedList<MethodDescriptor> descriptorListToAnalyze = ssjava.getSortedDescriptors();
+    Map<MethodDescriptor, Integer> mapMethodDescToParamCount =
+        new HashMap<MethodDescriptor, Integer>();
 
-    // current descriptors to visit in fixed-point interprocedural analysis,
-    // prioritized by
-    // dependency in the call graph
-    methodDescriptorsToVisitStack.clear();
+    next: for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      MethodDescriptor highestMethodDesc = (MethodDescriptor) iterator.next();
 
-    descriptorListToAnalyze.removeFirst();
+      NTuple<Descriptor> tempTuple = null;
 
-    Set<MethodDescriptor> methodDescriptorToVistSet = new HashSet<MethodDescriptor>();
-    methodDescriptorToVistSet.addAll(descriptorListToAnalyze);
+      if (getMethodSummary(highestMethodDesc).getPCLoc() != null) {
 
-    while (!descriptorListToAnalyze.isEmpty()) {
-      MethodDescriptor md = descriptorListToAnalyze.removeFirst();
-      methodDescriptorsToVisitStack.add(md);
-    }
+        Set<MethodDescriptor> methodDescSet =
+            mapHighestOverriddenMethodDescToMethodDescSet.get(highestMethodDesc);
 
-    // analyze scheduled methods until there are no more to visit
-    while (!methodDescriptorsToVisitStack.isEmpty()) {
-      // start to analyze leaf node
-      MethodDescriptor md = methodDescriptorsToVisitStack.pop();
+        if (methodDescSet.size() > 1) {
+          // System.out.println("---method desc set=" + methodDescSet + "  from=" +
+          // highestMethodDesc);
+        } else {
+          continue next;
+        }
 
-      SSJavaLattice<String> methodLattice =
-          new SSJavaLattice<String>(SSJavaAnalysis.TOP, SSJavaAnalysis.BOTTOM);
+        for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+          MethodDescriptor md = (MethodDescriptor) iterator2.next();
 
-      System.out.println();
-      System.out.println("SSJAVA: Inferencing the lattice from " + md);
+          FlowGraph flowGraph = getFlowGraph(md);
+          if (flowGraph == null) {
+            continue;
+          }
+          Set<FlowNode> paramNodeSet = flowGraph.getParamFlowNodeSet();
+          // System.out.println("###md=" + md + "   paramNodeSet=" + paramNodeSet);
 
-      analyzeMethodLattice(md, methodLattice);
+          CompositeLocation pcLOC = getMethodSummary(md).getPCLoc();
+          // System.out.println("---pcLOC=" + pcLOC);
 
-      SSJavaLattice<String> prevMethodLattice = getMethodLattice(md);
+          if (md.equals(highestMethodDesc)) {
+            mapHighestOverriddenMethodDescToPCLocTuple.put(highestMethodDesc,
+                translateToDescTuple(pcLOC.getTuple()));
+          }
 
-      if (!methodLattice.equals(prevMethodLattice)) {
+          if (!pcLOC.get(0).isTop()) {
 
-        setMethodLattice(md, methodLattice);
+            FlowNode pcFlowNode = flowGraph.getFlowNode(translateToDescTuple(pcLOC.getTuple()));
 
-        // results for callee changed, so enqueue dependents caller for
-        // further analysis
-        Iterator<MethodDescriptor> depsItr = ssjava.getDependents(md).iterator();
-        while (depsItr.hasNext()) {
-          MethodDescriptor methodNext = depsItr.next();
-          if (!methodDescriptorsToVisitStack.contains(methodNext)
-              && methodDescriptorToVistSet.contains(methodNext)) {
-            methodDescriptorsToVisitStack.add(methodNext);
+            int count = 0;
+            for (Iterator iterator3 = paramNodeSet.iterator(); iterator3.hasNext();) {
+              FlowNode paramNode = (FlowNode) iterator3.next();
+              if (flowGraph.getReachableSetFrom(pcFlowNode.getCurrentDescTuple().subList(0, 1))
+                  .contains(paramNode)) {
+                count++;
+              }
+            }
+            mapMethodDescToParamCount.put(md, count);
+
+          } else {
+
+            // the PC location is top
+            // if one of pcloc among the method inheritance chain has the TOP,
+            // all methods in the same chain should have the TOP.
+            mapHighestOverriddenMethodDescToPCLocTuple.remove(highestMethodDesc);
+            // System.out.println("highest=" + highestMethodDesc + "  HIGHEST PCLOC="
+            // + mapHighestOverriddenMethodDescToPCLocTuple.get(highestMethodDesc));
+
+            Set<NTuple<Descriptor>> descTupleSetLowerThanPC = new HashSet<NTuple<Descriptor>>();
+            for (Iterator iterator3 = paramNodeSet.iterator(); iterator3.hasNext();) {
+              FlowNode flowNode = (FlowNode) iterator3.next();
+              descTupleSetLowerThanPC.add(flowNode.getCurrentDescTuple());
+            }
+            mapHighestOverriddenMethodDescToSetLowerThanPCLoc.put(highestMethodDesc,
+                descTupleSetLowerThanPC);
+
+            continue next;
           }
         }
 
-      }
+        // identify which method in the inheritance chain has the highest PCLOC
+        // basically, finds a method that has the highest count or TOP location
+        int highestCount = -1;
+        MethodDescriptor methodDescHighestCount = null;
+        for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+          MethodDescriptor methodDesc = (MethodDescriptor) iterator2.next();
+          if (mapMethodDescToParamCount.containsKey(methodDesc)) {
+            int curCount = mapMethodDescToParamCount.get(methodDesc).intValue();
+            if (highestCount < curCount) {
+              highestCount = curCount;
+              methodDescHighestCount = methodDesc;
+            }
+          }
+        }
 
-    }
+        if (methodDescHighestCount != null) {
+          FlowGraph flowGraph = getFlowGraph(methodDescHighestCount);
+          CompositeLocation pcLOC = getMethodSummary(methodDescHighestCount).getPCLoc();
+          FlowNode pcFlowNode = flowGraph.getFlowNode(translateToDescTuple(pcLOC.getTuple()));
+          Set<FlowNode> reachableSet =
+              flowGraph.getReachableSetFrom(pcFlowNode.getCurrentDescTuple().subList(0, 1));
 
-  }
+          Set<FlowNode> reachableParamNodeSet = new HashSet<FlowNode>();
+          for (Iterator iterator3 = reachableSet.iterator(); iterator3.hasNext();) {
+            FlowNode flowNode = (FlowNode) iterator3.next();
+            if (flowGraph.isParameter(flowNode.getCurrentDescTuple())) {
+              reachableParamNodeSet.add(flowNode);
+            }
 
-  private void checkLatticesOfVirtualMethods(MethodDescriptor md) {
+          }
 
-    if (!md.isStatic()) {
-      Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
-      setPossibleCallees.addAll(ssjava.getCallGraph().getMethods(md));
+          Set<NTuple<Descriptor>> descTupleSetLowerThanPC = new HashSet<NTuple<Descriptor>>();
+          for (Iterator iterator2 = reachableParamNodeSet.iterator(); iterator2.hasNext();) {
+            FlowNode flowNode = (FlowNode) iterator2.next();
+            descTupleSetLowerThanPC.add(flowNode.getCurrentDescTuple());
+          }
 
-      for (Iterator iterator = setPossibleCallees.iterator(); iterator.hasNext();) {
-        MethodDescriptor mdCallee = (MethodDescriptor) iterator.next();
-        if (!md.equals(mdCallee)) {
-          checkConsistency(md, mdCallee);
+          // mapHighestOverriddenMethodDescToPCLocTuple.remove(highestMethodDesc);
+          mapHighestOverriddenMethodDescToSetLowerThanPCLoc.put(highestMethodDesc,
+              descTupleSetLowerThanPC);
         }
+
       }
 
+      // System.out.println("####################################");
+      // System.out.println("  highest=" + highestMethodDesc + "  HIGHEST PCLOC="
+      // + mapHighestOverriddenMethodDescToPCLocTuple.get(highestMethodDesc));
+      // System.out.println("  setLowerThanPCLoc="
+      // + mapHighestOverriddenMethodDescToSetLowerThanPCLoc.get(highestMethodDesc));
     }
 
   }
 
-  private void checkConsistency(MethodDescriptor md1, MethodDescriptor md2) {
+  private void calculateLowestReturnLocInheritance() {
 
-    // check that two lattice have the same relations between parameters(+PC
-    // LOC, RETURN LOC)
+    Set<MethodDescriptor> keySet = mapHighestOverriddenMethodDescToMethodDescSet.keySet();
 
-    MethodLocationInfo methodInfo1 = getMethodLocationInfo(md1);
+    Map<MethodDescriptor, Integer> mapMethodDescToParamCount =
+        new HashMap<MethodDescriptor, Integer>();
 
-    SSJavaLattice<String> lattice1 = getMethodLattice(md1);
-    SSJavaLattice<String> lattice2 = getMethodLattice(md2);
+    next: for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      MethodDescriptor highestMethodDesc = (MethodDescriptor) iterator.next();
 
-    Set<String> paramLocNameSet1 = methodInfo1.getParameterLocNameSet();
+      Set<MethodDescriptor> methodDescSet =
+          mapHighestOverriddenMethodDescToMethodDescSet.get(highestMethodDesc);
+
+      if (methodDescSet.size() > 1 && getMethodSummary(highestMethodDesc).getRETURNLoc() != null) {
+      } else {
+        continue next;
+      }
 
-    for (Iterator iterator = paramLocNameSet1.iterator(); iterator.hasNext();) {
-      String locName1 = (String) iterator.next();
-      for (Iterator iterator2 = paramLocNameSet1.iterator(); iterator2.hasNext();) {
-        String locName2 = (String) iterator2.next();
+      for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+        MethodDescriptor md = (MethodDescriptor) iterator2.next();
 
-        // System.out.println("COMPARE " + locName1 + " - " + locName2 + " "
-        // + lattice1.isGreaterThan(locName1, locName2) + "-"
-        // + lattice2.isGreaterThan(locName1, locName2));
+        FlowGraph flowGraph = getFlowGraph(md);
+        Set<FlowNode> paramNodeSet = flowGraph.getParamFlowNodeSet();
 
-        if (!locName1.equals(locName2)) {
+        CompositeLocation returnLoc = getMethodSummary(md).getRETURNLoc();
 
-          boolean r1 = lattice1.isGreaterThan(locName1, locName2);
-          boolean r2 = lattice2.isGreaterThan(locName1, locName2);
+        FlowNode returnFlowNode = flowGraph.getFlowNode(translateToDescTuple(returnLoc.getTuple()));
 
-          if (r1 != r2) {
-            throw new Error("The method " + md1 + " is not consistent with the method " + md2
-                + ".:: They have a different ordering relation between parameters " + locName1
-                + " and " + locName2 + ".");
+        int count = 0;
+        for (Iterator iterator3 = paramNodeSet.iterator(); iterator3.hasNext();) {
+          FlowNode paramNode = (FlowNode) iterator3.next();
+          if (flowGraph.getReachableSetFrom(paramNode.getCurrentDescTuple().subList(0, 1))
+              .contains(returnFlowNode)) {
+            count++;
+          }
+        }
+        mapMethodDescToParamCount.put(md, count);
+        // System.out.println("###returnLoc=" + returnLoc + "    count higher=" + count);
+      }
+
+      // identify which method in the inheritance chain has the highest PCLOC
+      // basically, finds a method that has the highest count or TOP location
+      int highestCount = -1;
+      MethodDescriptor methodDescHighestCount = null;
+      for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+        MethodDescriptor methodDesc = (MethodDescriptor) iterator2.next();
+        int curCount = mapMethodDescToParamCount.get(methodDesc).intValue();
+        if (highestCount < curCount) {
+          highestCount = curCount;
+          methodDescHighestCount = methodDesc;
+        }
+      }
+
+      if (methodDescHighestCount != null) {
+        FlowGraph flowGraph = getFlowGraph(methodDescHighestCount);
+        CompositeLocation returnLOC = getMethodSummary(methodDescHighestCount).getRETURNLoc();
+        NTuple<Descriptor> returnLocTuple = translateToDescTuple(returnLOC.getTuple());
+        FlowNode returnFlowNode = flowGraph.getFlowNode(returnLocTuple);
+
+        Set<FlowNode> curMethodParamNodeSet = flowGraph.getParamFlowNodeSet();
+        Set<NTuple<Descriptor>> descTupleSetHigherThanPC = new HashSet<NTuple<Descriptor>>();
+        for (Iterator iterator3 = curMethodParamNodeSet.iterator(); iterator3.hasNext();) {
+          FlowNode paramNode = (FlowNode) iterator3.next();
+          if (flowGraph.getReachableSetFrom(paramNode.getCurrentDescTuple().subList(0, 1))
+              .contains(returnFlowNode)) {
+            descTupleSetHigherThanPC.add(paramNode.getCurrentDescTuple());
           }
         }
 
+        mapHighestOverriddenMethodDescToReturnLocTuple.put(highestMethodDesc, returnLocTuple);
+        mapHighestOverriddenMethodDescToSetHigherThanRETURNLoc.put(highestMethodDesc,
+            descTupleSetHigherThanPC);
+
       }
+
+      // System.out.println("####################################");
+      // System.out.println("  highest=" + highestMethodDesc + "  LOWEST RETURNLOC="
+      // + mapHighestOverriddenMethodDescToReturnLocTuple.get(highestMethodDesc));
+      // System.out.println("  setHigherThanReturnLoc="
+      // + mapHighestOverriddenMethodDescToSetHigherThanRETURNLoc.get(highestMethodDesc));
+
     }
 
   }
 
-  private String getSymbol(int idx, FlowNode node) {
-    Descriptor desc = node.getDescTuple().get(idx);
-    return desc.getSymbol();
+  private void addMapHighestMethodDescToMethodDesc(MethodDescriptor highest, MethodDescriptor md) {
+    if (!mapHighestOverriddenMethodDescToMethodDescSet.containsKey(highest)) {
+      mapHighestOverriddenMethodDescToMethodDescSet.put(highest, new HashSet<MethodDescriptor>());
+    }
+    mapHighestOverriddenMethodDescToMethodDescSet.get(highest).add(md);
   }
 
-  private void analyzeMethodLattice(MethodDescriptor md, SSJavaLattice<String> methodLattice) {
+  private void DFSInheritanceTreeCalculatingHighestOverriddenMethod(ClassDescriptor cd) {
 
-    MethodLocationInfo methodInfo = getMethodLocationInfo(md);
+    // ClassDescriptor cd = node.getData();
 
-    // first take a look at method invocation nodes to newly added relations
-    // from the callee
-    analyzeLatticeMethodInvocationNode(md);
+    for (Iterator iterator = cd.getMethods(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      MethodDescriptor highestMethodDesc = getHighestOverriddenMethod(md.getClassDesc(), md);
+      mapMethodDescToHighestOverriddenMethodDesc.put(md, highestMethodDesc);
+      addMapHighestMethodDescToMethodDesc(highestMethodDesc, md);
 
-    // visit each node of method flow graph
-    FlowGraph fg = getFlowGraph(md);
-    Set<FlowNode> nodeSet = fg.getNodeSet();
+    }
 
-    // for the method lattice, we need to look at the first element of
-    // NTuple<Descriptor>
-    for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
-      FlowNode srcNode = (FlowNode) iterator.next();
+    // traverse children
+    Set<ClassDescriptor> children = getDirectSubClasses(cd);
+    for (Iterator iterator = children.iterator(); iterator.hasNext();) {
+      ClassDescriptor child = (ClassDescriptor) iterator.next();
+      DFSInheritanceTreeCalculatingHighestOverriddenMethod(child);
+    }
 
-      Set<FlowEdge> outEdgeSet = srcNode.getOutEdgeSet();
-      for (Iterator iterator2 = outEdgeSet.iterator(); iterator2.hasNext();) {
-        FlowEdge outEdge = (FlowEdge) iterator2.next();
-        FlowNode dstNode = outEdge.getDst();
+  }
 
-        NTuple<Descriptor> srcNodeTuple = srcNode.getDescTuple();
-        NTuple<Descriptor> dstNodeTuple = dstNode.getDescTuple();
+  private MethodDescriptor getHighestOverriddenMethod(ClassDescriptor curClassDesc,
+      MethodDescriptor curMethodDesc) {
+
+    // Node<ClassDescriptor> curNode = inheritanceTree.getTreeNode(curClassDesc);
+    // Node<ClassDescriptor> parentNode = curNode.getParent();
+    ClassDescriptor parentClassDesc = curClassDesc.getSuperDesc();
+
+    if (parentClassDesc != null) {
+      if (parentClassDesc.getMethodTable().contains(curMethodDesc.getSymbol())) {
+        Set<MethodDescriptor> methodDescSet =
+            parentClassDesc.getMethodTable().getSet(curMethodDesc.getSymbol());
+        for (Iterator iterator = methodDescSet.iterator(); iterator.hasNext();) {
+          MethodDescriptor md = (MethodDescriptor) iterator.next();
+          if (md.matches(curMethodDesc)) {
+            return getHighestOverriddenMethod(parentClassDesc, md);
+          }
+        }
+      }
+      // traverse to the parent!
+      return getHighestOverriddenMethod(parentClassDesc, curMethodDesc);
+    }
+    return curMethodDesc;
+  }
 
-        if (outEdge.getInitTuple().equals(srcNodeTuple)
-            && outEdge.getEndTuple().equals(dstNodeTuple)) {
+  private void buildInheritanceTree() {
 
-          if ((srcNodeTuple.size() > 1 && dstNodeTuple.size() > 1)
-              && srcNodeTuple.get(0).equals(dstNodeTuple.get(0))) {
+    DFSInheritanceTreeCalculatingHighestOverriddenMethod(rootClassDescriptor);
 
-            // value flows between fields
-            VarDescriptor varDesc = (VarDescriptor) srcNodeTuple.get(0);
-            ClassDescriptor varClassDesc = varDesc.getType().getClassDesc();
-            extractRelationFromFieldFlows(varClassDesc, srcNode, dstNode, 1);
+  }
 
-          } else {
-            // in this case, take a look at connected nodes at the local level
-            addRelationToLattice(md, methodLattice, srcNode, dstNode);
-          }
+  private void addInheritanceConstraintsToHierarchyGraph() {
+
+    // DFS the inheritance tree and propagates nodes/edges of parent to child
+
+    // Node<ClassDescriptor> rootNode = inheritanceTree.getRootNode();
+    DFSInheritanceTree(rootClassDescriptor);
+
+  }
+
+  private void DFSInheritanceTree(ClassDescriptor parentClassDescriptor) {
+
+    // ClassDescriptor parentClassDescriptor = parentNode.getData();
+
+    Set<ClassDescriptor> children = getDirectSubClasses(parentClassDescriptor);
+    for (Iterator iterator = children.iterator(); iterator.hasNext();) {
+      ClassDescriptor childClassDescriptor = (ClassDescriptor) iterator.next();
+
+      HierarchyGraph parentGraph = getHierarchyGraph(parentClassDescriptor);
+      HierarchyGraph childGraph = getHierarchyGraph(childClassDescriptor);
+
+      Set<HNode> parentNodeSet = parentGraph.getNodeSet();
+      for (Iterator iterator2 = parentNodeSet.iterator(); iterator2.hasNext();) {
+        HNode hNode = (HNode) iterator2.next();
+        childGraph.addNode(hNode);
+      }
+
+      // copies extra information from the parent hierarchy graph
+      Map<HNode, Set<HNode>> parentMergeNodeMap = parentGraph.getMapHNodetoMergeSet();
+      Map<HNode, Set<HNode>> childMergeNodeMap = childGraph.getMapHNodetoMergeSet();
+
+      Set<HNode> keySet = parentMergeNodeMap.keySet();
+      for (Iterator iterator2 = keySet.iterator(); iterator2.hasNext();) {
+        HNode parentKey = (HNode) iterator2.next();
+        if (!childMergeNodeMap.containsKey(parentKey)) {
+          childMergeNodeMap.put(parentKey, new HashSet<HNode>());
+        }
+        childMergeNodeMap.get(parentKey).addAll(parentMergeNodeMap.get(parentKey));
+      }
+
+      // copies nodes/edges from the parent class...
+      for (Iterator iterator2 = parentNodeSet.iterator(); iterator2.hasNext();) {
+        HNode parentHNode = (HNode) iterator2.next();
 
+        Set<HNode> parentIncomingHNode = parentGraph.getIncomingNodeSet(parentHNode);
+        Set<HNode> parentOutgoingHNode = parentGraph.getOutgoingNodeSet(parentHNode);
+
+        for (Iterator iterator3 = parentIncomingHNode.iterator(); iterator3.hasNext();) {
+          HNode inHNode = (HNode) iterator3.next();
+          childGraph.addEdge(inHNode.getDescriptor(), parentHNode.getDescriptor());
+        }
+
+        for (Iterator iterator3 = parentOutgoingHNode.iterator(); iterator3.hasNext();) {
+          HNode outHNode = (HNode) iterator3.next();
+          childGraph.addEdge(parentHNode.getDescriptor(), outHNode.getDescriptor());
         }
 
       }
 
-    }
+      // copies nodes/edges from parent methods to overridden methods
 
-    // grab the this location if the method use the 'this' reference
-    String thisLocSymbol = md.getThis().getSymbol();
-    if (methodLattice.getKeySet().contains(thisLocSymbol)) {
-      methodInfo.setThisLocName(thisLocSymbol);
-    }
+      for (Iterator iterator3 = childClassDescriptor.getMethods(); iterator3.hasNext();) {
+        MethodDescriptor childMethodDescriptor = (MethodDescriptor) iterator3.next();
 
-    // calculate a return location
-    if (!md.getReturnType().isVoid()) {
-      Set<FlowNode> returnNodeSet = fg.getReturnNodeSet();
-      Set<String> returnVarSymbolSet = new HashSet<String>();
+        MethodDescriptor parentMethodDesc =
+            getParentMethodDesc(childMethodDescriptor.getClassDesc(), childMethodDescriptor);
+
+        if (parentMethodDesc != null) {
+
+          HierarchyGraph parentMethodGraph = getHierarchyGraph(parentMethodDesc);
+          HierarchyGraph childMethodGraph = getHierarchyGraph(childMethodDescriptor);
+
+          Set<HNode> parentMethodNodeSet = parentMethodGraph.getNodeSet();
+          for (Iterator iterator2 = parentMethodNodeSet.iterator(); iterator2.hasNext();) {
+            HNode hNode = (HNode) iterator2.next();
+            childMethodGraph.addNode(hNode);
+          }
+
+          // copies extra information from the parent hierarchy graph
+          Map<HNode, Set<HNode>> parentMethodMergeNodeMap =
+              parentMethodGraph.getMapHNodetoMergeSet();
+          Map<HNode, Set<HNode>> childMethodMergeNodeMap = childMethodGraph.getMapHNodetoMergeSet();
+
+          Set<HNode> methodKeySet = parentMethodMergeNodeMap.keySet();
+          for (Iterator iterator2 = methodKeySet.iterator(); iterator2.hasNext();) {
+            HNode parentKey = (HNode) iterator2.next();
+            if (!childMethodMergeNodeMap.containsKey(parentKey)) {
+              childMethodMergeNodeMap.put(parentKey, new HashSet<HNode>());
+            }
+            childMethodMergeNodeMap.get(parentKey).addAll(parentMethodMergeNodeMap.get(parentKey));
+          }
+
+          // copies nodes/edges from the parent method...
+          for (Iterator iterator2 = parentMethodGraph.getNodeSet().iterator(); iterator2.hasNext();) {
+            HNode parentHNode = (HNode) iterator2.next();
+
+            Set<HNode> parentIncomingHNode = parentMethodGraph.getIncomingNodeSet(parentHNode);
+            Set<HNode> parentOutgoingHNode = parentMethodGraph.getOutgoingNodeSet(parentHNode);
+
+            for (Iterator iterator4 = parentIncomingHNode.iterator(); iterator4.hasNext();) {
+              HNode inHNode = (HNode) iterator4.next();
+              childMethodGraph.addEdge(inHNode, parentHNode);
+            }
+
+            for (Iterator iterator4 = parentOutgoingHNode.iterator(); iterator4.hasNext();) {
+              HNode outHNode = (HNode) iterator4.next();
+              childMethodGraph.addEdge(parentHNode, outHNode);
+            }
+
+          }
+
+        }
 
-      for (Iterator iterator = returnNodeSet.iterator(); iterator.hasNext();) {
-        FlowNode rtrNode = (FlowNode) iterator.next();
-        String localSymbol = rtrNode.getDescTuple().get(0).getSymbol();
-        returnVarSymbolSet.add(localSymbol);
-      }
-
-      String returnGLB = methodLattice.getGLB(returnVarSymbolSet);
-      if (returnGLB.equals(SSJavaAnalysis.BOTTOM)) {
-        // need to insert a new location in-between the bottom and all locations
-        // that is directly connected to the bottom
-        String returnNewLocationSymbol = "Loc" + (SSJavaLattice.seed++);
-        methodLattice.insertNewLocationAtOneLevelHigher(returnGLB, returnNewLocationSymbol);
-        methodInfo.setReturnLocName(returnNewLocationSymbol);
-      } else {
-        methodInfo.setReturnLocName(returnGLB);
       }
+
+      DFSInheritanceTree(childClassDescriptor);
     }
 
   }
 
-  private void analyzeLatticeMethodInvocationNode(MethodDescriptor mdCaller) {
+  public MethodDescriptor getParentMethodDesc(ClassDescriptor classDesc, MethodDescriptor methodDesc) {
+
+    // Node<ClassDescriptor> childNode = inheritanceTree.getTreeNode(classDesc);
+    ClassDescriptor parentClassDesc = classDesc.getSuperDesc();
+    // Node<ClassDescriptor> parentNode = childNode.getParent();
+
+    if (parentClassDesc != null) {
+      // ClassDescriptor parentClassDesc = parentNode.getData();
+      if (parentClassDesc.getMethodTable().contains(methodDesc.getSymbol())) {
+        Set<MethodDescriptor> methodDescSet =
+            parentClassDesc.getMethodTable().getSet(methodDesc.getSymbol());
+        for (Iterator iterator = methodDescSet.iterator(); iterator.hasNext();) {
+          MethodDescriptor md = (MethodDescriptor) iterator.next();
+          if (md.matches(methodDesc)) {
+            return md;
+          }
+        }
+      }
 
-    // the transformation for a call site propagates all relations between
-    // parameters from the callee
-    // if the method is virtual, it also grab all relations from any possible
-    // callees
+      // traverse to the parent!
+      getParentMethodDesc(parentClassDesc, methodDesc);
 
-    Set<MethodInvokeNode> setMethodInvokeNode =
-        mapMethodDescriptorToMethodInvokeNodeSet.get(mdCaller);
-    if (setMethodInvokeNode != null) {
+    }
 
-      for (Iterator iterator = setMethodInvokeNode.iterator(); iterator.hasNext();) {
-        MethodInvokeNode min = (MethodInvokeNode) iterator.next();
-        MethodDescriptor mdCallee = min.getMethod();
-        Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
-        if (mdCallee.isStatic()) {
-          setPossibleCallees.add(mdCallee);
+    return null;
+  }
+
+  private void checkReturnNodes() {
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+
+      if (md.getReturnType() != null && !md.getReturnType().isVoid()) {
+        checkFlowNodeReturnThisField(md);
+      }
+      // // in this case, this method will return the composite location that starts with 'this'
+      // FlowGraph flowGraph = getFlowGraph(md);
+      // Set<FlowNode> returnNodeSet = flowGraph.getReturnNodeSet();
+      // }
+
+    }
+
+  }
+
+  private void addSuperClasses(ClassDescriptor cd) {
+    ClassDescriptor parentClassDesc = cd.getSuperDesc();
+    if (parentClassDesc != null) {
+      toanalyze_classDescSet.add(parentClassDesc);
+      addSuperClasses(parentClassDesc);
+    }
+  }
+
+  private void updateFlowGraph() {
+
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+      if (state.SSJAVADEBUG) {
+        System.out.println();
+        System.out.println("SSJAVA: Updating a flow graph: " + md);
+        propagateFlowsFromCalleesWithNoCompositeLocation(md);
+      }
+
+      Set<FlowNode> nodeSet = getFlowGraph(md).getNodeSet();
+      for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+        FlowNode flowNode = (FlowNode) iterator.next();
+        NTuple<Descriptor> descTuple = flowNode.getCurrentDescTuple();
+        NTuple<Location> locTuple = translateToLocTuple(md, descTuple);
+        for (int i = 0; i < locTuple.size(); i++) {
+          Location loc = locTuple.get(i);
+          if (loc.getDescriptor() instanceof ClassDescriptor) {
+            ClassDescriptor classDesc = (ClassDescriptor) loc.getDescriptor();
+            toanalyze_classDescSet.add(classDesc);
+            addSuperClasses(classDesc);
+          } else if (loc.getDescriptor() instanceof MethodDescriptor) {
+            toanalyze_classDescSet.add(((MethodDescriptor) loc.getDescriptor()).getClassDesc());
+          }
+        }
+
+      }
+
+    }
+  }
+
+  public Map<NTuple<Descriptor>, NTuple<Descriptor>> getMapCallerArgToCalleeParam(
+      MethodInvokeNode min) {
+
+    if (!mapMethodInvokeNodeToMapCallerArgToCalleeArg.containsKey(min)) {
+      mapMethodInvokeNodeToMapCallerArgToCalleeArg.put(min,
+          new HashMap<NTuple<Descriptor>, NTuple<Descriptor>>());
+    }
+
+    return mapMethodInvokeNodeToMapCallerArgToCalleeArg.get(min);
+  }
+
+  public void addMapCallerArgToCalleeParam(MethodInvokeNode min, NTuple<Descriptor> callerArg,
+      NTuple<Descriptor> calleeParam) {
+    getMapCallerArgToCalleeParam(min).put(callerArg, calleeParam);
+  }
+
+  private void assignCompositeLocation() {
+    calculateGlobalValueFlowCompositeLocation();
+    translateCompositeLocationAssignmentToFlowGraph();
+  }
+
+  private void translateCompositeLocationAssignmentToFlowGraph() {
+    System.out.println("\nSSJAVA: Translate composite location assignments to flow graphs:");
+    MethodDescriptor methodEventLoopDesc = ssjava.getMethodContainingSSJavaLoop();
+    translateCompositeLocationAssignmentToFlowGraph(methodEventLoopDesc);
+  }
+
+  private void translateCompositeLocationAssignmentToFlowGraph2() {
+    System.out.println("\nSSJAVA: Translate composite location assignments to flow graphs:");
+    MethodDescriptor methodEventLoopDesc = ssjava.getMethodContainingSSJavaLoop();
+    translateCompositeLocationAssignmentToFlowGraph(methodEventLoopDesc);
+  }
+
+  private void addAdditionalOrderingConstraints() {
+    System.out.println("\nSSJAVA: Add addtional ordering constriants:");
+    MethodDescriptor methodEventLoopDesc = ssjava.getMethodContainingSSJavaLoop();
+    addAddtionalOrderingConstraints(methodEventLoopDesc);
+    // calculateReturnHolderLocation();
+  }
+
+  private void calculateReturnHolderLocation() {
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+
+      FlowGraph fg = getFlowGraph(md);
+      Set<FlowNode> nodeSet = fg.getNodeSet();
+      for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+        FlowNode flowNode = (FlowNode) iterator.next();
+        if (flowNode.isFromHolder()) {
+          calculateCompositeLocationFromFlowGraph(md, flowNode);
+        }
+      }
+
+    }
+  }
+
+  private void updateCompositeLocationAssignments() {
+
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+
+      // System.out.println("\n#updateCompositeLocationAssignments=" + md);
+
+      FlowGraph flowGraph = getFlowGraph(md);
+
+      MethodSummary methodSummary = getMethodSummary(md);
+
+      Set<FlowNode> nodeSet = flowGraph.getNodeSet();
+      for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+        FlowNode node = (FlowNode) iterator.next();
+        // System.out.println("-node=" + node + "   node.getDescTuple=" + node.getDescTuple());
+        if (node.getCompositeLocation() != null) {
+          CompositeLocation compLoc = node.getCompositeLocation();
+          CompositeLocation updatedCompLoc = updateCompositeLocation(compLoc);
+          node.setCompositeLocation(updatedCompLoc);
+          // System.out.println("---updatedCompLoc1=" + updatedCompLoc);
         } else {
-          setPossibleCallees.addAll(ssjava.getCallGraph().getMethods(mdCallee));
+          NTuple<Descriptor> descTuple = node.getDescTuple();
+          // System.out.println("update desc=" + descTuple);
+          CompositeLocation compLoc = convertToCompositeLocation(md, descTuple);
+          compLoc = updateCompositeLocation(compLoc);
+          node.setCompositeLocation(compLoc);
+          // System.out.println("---updatedCompLoc2=" + compLoc);
         }
 
-        for (Iterator iterator2 = setPossibleCallees.iterator(); iterator2.hasNext();) {
-          MethodDescriptor possibleMdCallee = (MethodDescriptor) iterator2.next();
-          propagateRelationToCaller(min, mdCaller, possibleMdCallee);
+        if (node.isDeclaratonNode()) {
+          Descriptor localVarDesc = node.getDescTuple().get(0);
+          CompositeLocation compLoc = updateCompositeLocation(node.getCompositeLocation());
+          methodSummary.addMapVarNameToInferCompLoc(localVarDesc, compLoc);
+        }
+      }
+
+      // update PCLOC and RETURNLOC if they have a composite location assignment
+      if (methodSummary.getRETURNLoc() != null) {
+        methodSummary.setRETURNLoc(updateCompositeLocation(methodSummary.getRETURNLoc()));
+      }
+      if (methodSummary.getPCLoc() != null) {
+        methodSummary.setPCLoc(updateCompositeLocation(methodSummary.getPCLoc()));
+      }
+
+    }
+
+  }
+
+  private CompositeLocation updateCompositeLocation(CompositeLocation compLoc) {
+    CompositeLocation updatedCompLoc = new CompositeLocation();
+    for (int i = 0; i < compLoc.getSize(); i++) {
+      Location loc = compLoc.get(i);
+      String nodeIdentifier = loc.getLocIdentifier();
+      Descriptor enclosingDesc = loc.getDescriptor();
+      String locName;
+      if (!enclosingDesc.equals(GLOBALDESC)) {
+        LocationSummary locSummary = getLocationSummary(enclosingDesc);
+        // HierarchyGraph scGraph = getSkeletonCombinationHierarchyGraph(enclosingDesc);
+        HierarchyGraph scGraph = getSimpleHierarchyGraph(enclosingDesc);
+        if (scGraph != null) {
+          HNode curNode = scGraph.getCurrentHNode(nodeIdentifier);
+          // System.out.println("nodeID=" + nodeIdentifier + " curNode=" + curNode
+          // + "  enclosingDesc=" + enclosingDesc);
+          if (curNode != null) {
+            nodeIdentifier = curNode.getName();
+          }
+        }
+        locName = locSummary.getLocationName(nodeIdentifier);
+      } else {
+        locName = nodeIdentifier;
+      }
+      Location updatedLoc = new Location(enclosingDesc, locName);
+      updatedCompLoc.addLocation(updatedLoc);
+    }
+
+    return updatedCompLoc;
+  }
+
+  private void translateCompositeLocationAssignmentToFlowGraph(MethodDescriptor mdCaller) {
+
+    // System.out.println("\n\n###translateCompositeLocationAssignmentToFlowGraph mdCaller="
+    // + mdCaller);
+
+    // First, assign a composite location to a node in the flow graph
+    GlobalFlowGraph callerGlobalFlowGraph = getSubGlobalFlowGraph(mdCaller);
+
+    FlowGraph callerFlowGraph = getFlowGraph(mdCaller);
+    Map<Location, CompositeLocation> callerMapLocToCompLoc =
+        callerGlobalFlowGraph.getMapLocationToInferCompositeLocation();
+
+    Set<Location> methodLocSet = callerMapLocToCompLoc.keySet();
+    for (Iterator iterator = methodLocSet.iterator(); iterator.hasNext();) {
+      Location methodLoc = (Location) iterator.next();
+      if (methodLoc.getDescriptor().equals(mdCaller)) {
+        CompositeLocation inferCompLoc = callerMapLocToCompLoc.get(methodLoc);
+        assignCompositeLocationToFlowGraph(callerFlowGraph, methodLoc, inferCompLoc);
+      }
+    }
+
+    Set<MethodInvokeNode> minSet = mapMethodDescriptorToMethodInvokeNodeSet.get(mdCaller);
+
+    Set<MethodDescriptor> calleeSet = new HashSet<MethodDescriptor>();
+    for (Iterator iterator = minSet.iterator(); iterator.hasNext();) {
+      MethodInvokeNode min = (MethodInvokeNode) iterator.next();
+      // need to translate a composite location that is started with the base
+      // tuple of 'min'.
+      translateMapLocationToInferCompositeLocationToCalleeGraph(callerGlobalFlowGraph, min);
+      MethodDescriptor mdCallee = min.getMethod();
+      calleeSet.add(mdCallee);
+
+    }
+
+    for (Iterator iterator = calleeSet.iterator(); iterator.hasNext();) {
+      MethodDescriptor callee = (MethodDescriptor) iterator.next();
+      translateCompositeLocationAssignmentToFlowGraph(callee);
+    }
+
+  }
+
+  private void addAddtionalOrderingConstraints(MethodDescriptor mdCaller) {
+
+    // First, assign a composite location to a node in the flow graph
+    GlobalFlowGraph callerGlobalFlowGraph = getSubGlobalFlowGraph(mdCaller);
+
+    FlowGraph callerFlowGraph = getFlowGraph(mdCaller);
+    Map<Location, CompositeLocation> callerMapLocToCompLoc =
+        callerGlobalFlowGraph.getMapLocationToInferCompositeLocation();
+    Set<Location> methodLocSet = callerMapLocToCompLoc.keySet();
+
+    Set<MethodInvokeNode> minSet = mapMethodDescriptorToMethodInvokeNodeSet.get(mdCaller);
+
+    Set<MethodDescriptor> calleeSet = new HashSet<MethodDescriptor>();
+    for (Iterator iterator = minSet.iterator(); iterator.hasNext();) {
+      MethodInvokeNode min = (MethodInvokeNode) iterator.next();
+      MethodDescriptor mdCallee = min.getMethod();
+      calleeSet.add(mdCallee);
+
+      //
+      // add an additional ordering constraint
+      // if the first element of a parameter composite location matches 'this' reference,
+      // the corresponding argument in the caller is required to be higher than the translated
+      // parameter location in the caller lattice
+      // TODO
+      // addOrderingConstraintFromCompLocParamToArg(mdCaller, min);
+
+      //
+      // update return flow nodes in the caller
+      CompositeLocation returnLoc = getMethodSummary(mdCallee).getRETURNLoc();
+      // System.out.println("### min=" + min.printNode(0) + "  returnLoc=" + returnLoc);
+      if (returnLoc != null && returnLoc.get(0).getLocDescriptor().equals(mdCallee.getThis())
+          && returnLoc.getSize() > 1) {
+        // System.out.println("###RETURN COMP LOC=" + returnLoc);
+        NTuple<Location> returnLocTuple = returnLoc.getTuple();
+        NTuple<Descriptor> baseTuple = mapMethodInvokeNodeToBaseTuple.get(min);
+        // System.out.println("###basetuple=" + baseTuple);
+        NTuple<Descriptor> newReturnTuple = baseTuple.clone();
+        for (int i = 1; i < returnLocTuple.size(); i++) {
+          newReturnTuple.add(returnLocTuple.get(i).getLocDescriptor());
+        }
+        // System.out.println("###NEW RETURN TUPLE FOR CALLER=" + newReturnTuple);
+
+        FlowReturnNode holderNode = callerFlowGraph.getFlowReturnNode(min);
+        NodeTupleSet holderTupleSet =
+            getNodeTupleSetFromReturnNode(getFlowGraph(mdCaller), holderNode);
+
+        callerFlowGraph.getFlowReturnNode(min).setNewTuple(newReturnTuple);
+
+        // then need to remove old constraints
+        // TODO SAT
+        // System.out.println("###REMOVE OLD CONSTRAINTS=" + holderNode);
+        for (Iterator<NTuple<Descriptor>> iter = holderTupleSet.iterator(); iter.hasNext();) {
+          NTuple<Descriptor> tupleFromHolder = iter.next();
+          Set<FlowEdge> holderOutEdge = callerFlowGraph.getOutEdgeSet(holderNode);
+          for (Iterator iterator2 = holderOutEdge.iterator(); iterator2.hasNext();) {
+            FlowEdge outEdge = (FlowEdge) iterator2.next();
+            NTuple<Descriptor> toberemovedTuple = outEdge.getEndTuple();
+            // System.out.println("---remove " + tupleFromHolder + " -> " + toberemovedTuple);
+            callerFlowGraph.removeEdge(tupleFromHolder, toberemovedTuple);
+          }
+        }
+
+      } else {
+        // if the return loc set was empty and later pcloc was connected to the return loc
+        // need to make sure that return loc reflects to this changes.
+        FlowReturnNode flowReturnNode = callerFlowGraph.getFlowReturnNode(min);
+        if (flowReturnNode != null && flowReturnNode.getReturnTupleSet().isEmpty()) {
+
+          if (needToUpdateReturnLocHolder(min.getMethod(), flowReturnNode)) {
+            NTuple<Descriptor> baseTuple = mapMethodInvokeNodeToBaseTuple.get(min);
+            NTuple<Descriptor> newReturnTuple = baseTuple.clone();
+            flowReturnNode.addTuple(newReturnTuple);
+          }
+
+        }
+
+      }
+
+    }
+
+    for (Iterator iterator = calleeSet.iterator(); iterator.hasNext();) {
+      MethodDescriptor callee = (MethodDescriptor) iterator.next();
+      addAddtionalOrderingConstraints(callee);
+    }
+
+  }
+
+  private boolean needToUpdateReturnLocHolder(MethodDescriptor mdCallee,
+      FlowReturnNode flowReturnNode) {
+    FlowGraph fg = getFlowGraph(mdCallee);
+    MethodSummary summary = getMethodSummary(mdCallee);
+    CompositeLocation returnCompLoc = summary.getRETURNLoc();
+    NTuple<Descriptor> returnDescTuple = translateToDescTuple(returnCompLoc.getTuple());
+    Set<FlowNode> incomingNodeToReturnNode =
+        fg.getIncomingFlowNodeSet(fg.getFlowNode(returnDescTuple));
+    for (Iterator iterator = incomingNodeToReturnNode.iterator(); iterator.hasNext();) {
+      FlowNode inNode = (FlowNode) iterator.next();
+      if (inNode.getDescTuple().get(0).equals(mdCallee.getThis())) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  private void addMapMethodDescToMethodInvokeNodeSet(MethodInvokeNode min) {
+    MethodDescriptor md = min.getMethod();
+    if (!mapMethodDescToMethodInvokeNodeSet.containsKey(md)) {
+      mapMethodDescToMethodInvokeNodeSet.put(md, new HashSet<MethodInvokeNode>());
+    }
+    mapMethodDescToMethodInvokeNodeSet.get(md).add(min);
+  }
+
+  private Set<MethodInvokeNode> getMethodInvokeNodeSetByMethodDesc(MethodDescriptor md) {
+    if (!mapMethodDescToMethodInvokeNodeSet.containsKey(md)) {
+      mapMethodDescToMethodInvokeNodeSet.put(md, new HashSet<MethodInvokeNode>());
+    }
+    return mapMethodDescToMethodInvokeNodeSet.get(md);
+  }
+
+  public void assignCompositeLocationToFlowGraph(FlowGraph flowGraph, Location loc,
+      CompositeLocation inferCompLoc) {
+    Descriptor localDesc = loc.getLocDescriptor();
+
+    Set<FlowNode> nodeSet = flowGraph.getNodeSet();
+    for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+      FlowNode node = (FlowNode) iterator.next();
+      if (node.getDescTuple().startsWith(localDesc)
+          && !node.getDescTuple().get(0).equals(LITERALDESC)) {
+        // need to assign the inferred composite location to this node
+        CompositeLocation newCompLoc = generateCompositeLocation(node.getDescTuple(), inferCompLoc);
+        node.setCompositeLocation(newCompLoc);
+        // System.out.println("SET Node=" + node + "  inferCompLoc=" + newCompLoc);
+      }
+    }
+  }
+
+  private CompositeLocation generateCompositeLocation(NTuple<Descriptor> nodeDescTuple,
+      CompositeLocation inferCompLoc) {
+
+    // System.out.println("generateCompositeLocation=" + nodeDescTuple + " with inferCompLoc="
+    // + inferCompLoc);
+
+    MethodDescriptor md = (MethodDescriptor) inferCompLoc.get(0).getDescriptor();
+
+    CompositeLocation newCompLoc = new CompositeLocation();
+    for (int i = 0; i < inferCompLoc.getSize(); i++) {
+      newCompLoc.addLocation(inferCompLoc.get(i));
+    }
+
+    Descriptor lastDescOfPrefix = nodeDescTuple.get(0);
+    Descriptor enclosingDescriptor;
+    if (lastDescOfPrefix instanceof InterDescriptor) {
+      enclosingDescriptor = getFlowGraph(md).getEnclosingDescriptor(lastDescOfPrefix);
+    } else {
+      enclosingDescriptor = ((VarDescriptor) lastDescOfPrefix).getType().getClassDesc();
+    }
+
+    for (int i = 1; i < nodeDescTuple.size(); i++) {
+      Descriptor desc = nodeDescTuple.get(i);
+      Location locElement = new Location(enclosingDescriptor, desc);
+      newCompLoc.addLocation(locElement);
+
+      enclosingDescriptor = ((FieldDescriptor) desc).getClassDescriptor();
+    }
+
+    return newCompLoc;
+  }
+
+  private void translateMapLocationToInferCompositeLocationToCalleeGraph(
+      GlobalFlowGraph callerGraph, MethodInvokeNode min) {
+
+    MethodDescriptor mdCallee = min.getMethod();
+    MethodDescriptor mdCaller = callerGraph.getMethodDescriptor();
+    Map<Location, CompositeLocation> callerMapLocToCompLoc =
+        callerGraph.getMapLocationToInferCompositeLocation();
+
+    Map<Integer, NTuple<Descriptor>> mapIdxToArgTuple = mapMethodInvokeNodeToArgIdxMap.get(min);
+
+    FlowGraph calleeFlowGraph = getFlowGraph(mdCallee);
+    GlobalFlowGraph calleeGlobalGraph = getSubGlobalFlowGraph(mdCallee);
+
+    NTuple<Location> baseLocTuple = null;
+    if (mapMethodInvokeNodeToBaseTuple.containsKey(min)) {
+      baseLocTuple = translateToLocTuple(mdCaller, mapMethodInvokeNodeToBaseTuple.get(min));
+    }
+
+    // System.out.println("\n-#translate caller=" + mdCaller + " infer composite loc to callee="
+    // + mdCallee + " baseLocTuple=" + baseLocTuple);
+
+    Set<Location> keySet = callerMapLocToCompLoc.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Location key = (Location) iterator.next();
+      CompositeLocation callerCompLoc = callerMapLocToCompLoc.get(key);
+
+      if (!key.getDescriptor().equals(mdCaller)) {
+
+        CompositeLocation newCalleeCompLoc;
+        if (baseLocTuple != null && callerCompLoc.getTuple().startsWith(baseLocTuple)) {
+          // System.out.println("-----need to translate callerCompLoc=" + callerCompLoc
+          // + " with baseTuple=" + baseLocTuple);
+          newCalleeCompLoc =
+              translateCompositeLocationToCallee(callerCompLoc, baseLocTuple, mdCallee);
+
+          calleeGlobalGraph.addMapLocationToInferCompositeLocation(key, newCalleeCompLoc);
+          // System.out.println("1---key=" + key + "  callerCompLoc=" + callerCompLoc
+          // + "  newCalleeCompLoc=" + newCalleeCompLoc);
+          // System.out.println("-----caller=" + mdCaller + "    callee=" + mdCallee);
+          if (!newCalleeCompLoc.get(0).getDescriptor().equals(mdCallee)) {
+            System.exit(0);
+          }
+
+          // System.out.println("-----baseLoctuple=" + baseLocTuple);
+        } else {
+          // check if it is the global access
+          Location compLocFirstElement = callerCompLoc.getTuple().get(0);
+          if (compLocFirstElement.getDescriptor().equals(mdCallee)
+              && compLocFirstElement.getLocDescriptor().equals(GLOBALDESC)) {
+
+            newCalleeCompLoc = new CompositeLocation();
+            Location newMethodLoc = new Location(mdCallee, GLOBALDESC);
+
+            newCalleeCompLoc.addLocation(newMethodLoc);
+            for (int i = 1; i < callerCompLoc.getSize(); i++) {
+              newCalleeCompLoc.addLocation(callerCompLoc.get(i));
+            }
+            calleeGlobalGraph.addMapLocationToInferCompositeLocation(key, newCalleeCompLoc);
+            // System.out.println("2---key=" + key + "  callerCompLoc=" + callerCompLoc
+            // + "  newCalleeCompLoc=" + newCalleeCompLoc);
+            // System.out.println("-----caller=" + mdCaller + "    callee=" + mdCallee);
+
+          } else {
+            int paramIdx = getParamIdx(callerCompLoc, mapIdxToArgTuple);
+            if (paramIdx == -1) {
+              // here, the first element of the current composite location comes from the current
+              // callee
+              // so transfer the same composite location to the callee
+              if (!calleeGlobalGraph.contrainsInferCompositeLocationMapKey(key)) {
+                if (callerCompLoc.get(0).getDescriptor().equals(mdCallee)) {
+                  // System.out.println("3---key=" + key + "  callerCompLoc=" + callerCompLoc
+                  // + "  newCalleeCompLoc=" + callerCompLoc);
+                  // System.out.println("-----caller=" + mdCaller + "    callee=" + mdCallee);
+                  calleeGlobalGraph.addMapLocationToInferCompositeLocation(key, callerCompLoc);
+                } else {
+                  // System.out.println("3---SKIP key=" + key + " callerCompLoc=" + callerCompLoc);
+                }
+              }
+              continue;
+            }
+
+            // It is the case where two parameters have relative orderings between them by having
+            // composite locations
+            // if we found the param idx, it means that the first part of the caller composite
+            // location corresponds to the one of arguments.
+            // for example, if the caller argument is <<caller.this>,<Decoder.br>>
+            // and the current caller composite location mapping
+            // <<caller.this>,<Decoder.br>,<Br.value>>
+            // and the parameter which matches with the caller argument is 'Br brParam'
+            // then, the translated callee composite location will be <<callee.brParam>,<Br.value>>
+            NTuple<Descriptor> argTuple = mapIdxToArgTuple.get(paramIdx);
+
+            FlowNode paramFlowNode = calleeFlowGraph.getParamFlowNode(paramIdx);
+            NTuple<Location> paramLocTuple =
+                translateToLocTuple(mdCallee, paramFlowNode.getDescTuple());
+            newCalleeCompLoc = new CompositeLocation();
+            for (int i = 0; i < paramLocTuple.size(); i++) {
+              newCalleeCompLoc.addLocation(paramLocTuple.get(i));
+            }
+            for (int i = argTuple.size(); i < callerCompLoc.getSize(); i++) {
+              newCalleeCompLoc.addLocation(callerCompLoc.get(i));
+            }
+            calleeGlobalGraph.addMapLocationToInferCompositeLocation(key, newCalleeCompLoc);
+            // System.out.println("4---key=" + key + "  callerCompLoc=" + callerCompLoc
+            // + "  newCalleeCompLoc=" + newCalleeCompLoc);
+            // System.out.println("-----caller=" + mdCaller + "    callee=" + mdCallee);
+
+          }
+
+        }
+
+      }
+    }
+
+    // System.out.println("#ASSIGN COMP LOC TO CALLEE PARAMS: callee=" + mdCallee + "  caller="
+    // + mdCaller);
+    // If the location of an argument has a composite location
+    // need to assign a proper composite location to the corresponding callee parameter
+    Set<Integer> idxSet = mapIdxToArgTuple.keySet();
+    for (Iterator iterator = idxSet.iterator(); iterator.hasNext();) {
+      Integer idx = (Integer) iterator.next();
+
+      if (idx == 0 && !min.getMethod().isStatic()) {
+        continue;
+      }
+
+      NTuple<Descriptor> argTuple = mapIdxToArgTuple.get(idx);
+      // System.out.println("-argTuple=" + argTuple + "   idx=" + idx);
+      if (argTuple.size() > 0) {
+        // check if an arg tuple has been already assigned to a composite location
+        NTuple<Location> argLocTuple = translateToLocTuple(mdCaller, argTuple);
+        Location argLocalLoc = argLocTuple.get(0);
+
+        // if (!isPrimitiveType(argTuple)) {
+        if (callerMapLocToCompLoc.containsKey(argLocalLoc)) {
+
+          CompositeLocation callerCompLoc = callerMapLocToCompLoc.get(argLocalLoc);
+          for (int i = 1; i < argLocTuple.size(); i++) {
+            callerCompLoc.addLocation(argLocTuple.get(i));
+          }
+
+          // System.out.println("---callerCompLoc=" + callerCompLoc);
+
+          // if (baseLocTuple != null && callerCompLoc.getTuple().startsWith(baseLocTuple)) {
+
+          FlowNode calleeParamFlowNode = calleeFlowGraph.getParamFlowNode(idx);
+
+          NTuple<Descriptor> calleeParamDescTuple = calleeParamFlowNode.getDescTuple();
+          NTuple<Location> calleeParamLocTuple =
+              translateToLocTuple(mdCallee, calleeParamDescTuple);
+
+          int refParamIdx = getParamIdx(callerCompLoc, mapIdxToArgTuple);
+          // System.out.println("-----paramIdx=" + refParamIdx);
+          if (refParamIdx == 0 && !mdCallee.isStatic()) {
+
+            // System.out.println("-------need to translate callerCompLoc=" + callerCompLoc
+            // + " with baseTuple=" + baseLocTuple + "   calleeParamLocTuple="
+            // + calleeParamLocTuple);
+
+            CompositeLocation newCalleeCompLoc =
+                translateCompositeLocationToCallee(callerCompLoc, baseLocTuple, mdCallee);
+
+            calleeGlobalGraph.addMapLocationToInferCompositeLocation(calleeParamLocTuple.get(0),
+                newCalleeCompLoc);
+
+            // System.out.println("---------key=" + calleeParamLocTuple.get(0) + "  callerCompLoc="
+            // + callerCompLoc + "  newCalleeCompLoc=" + newCalleeCompLoc);
+
+          } else if (refParamIdx != -1) {
+            // the first element of an argument composite location matches with one of paramtere
+            // composite locations
+
+            // System.out.println("-------param match case=");
+
+            NTuple<Descriptor> argTupleRef = mapIdxToArgTuple.get(refParamIdx);
+            FlowNode refParamFlowNode = calleeFlowGraph.getParamFlowNode(refParamIdx);
+            NTuple<Location> refParamLocTuple =
+                translateToLocTuple(mdCallee, refParamFlowNode.getDescTuple());
+
+            // System.out.println("---------refParamLocTuple=" + refParamLocTuple
+            // + "  from argTupleRef=" + argTupleRef);
+
+            CompositeLocation newCalleeCompLoc = new CompositeLocation();
+            for (int i = 0; i < refParamLocTuple.size(); i++) {
+              newCalleeCompLoc.addLocation(refParamLocTuple.get(i));
+            }
+            for (int i = argTupleRef.size(); i < callerCompLoc.getSize(); i++) {
+              newCalleeCompLoc.addLocation(callerCompLoc.get(i));
+            }
+
+            calleeGlobalGraph.addMapLocationToInferCompositeLocation(calleeParamLocTuple.get(0),
+                newCalleeCompLoc);
+
+            calleeParamFlowNode.setCompositeLocation(newCalleeCompLoc);
+            // System.out.println("-----------key=" + calleeParamLocTuple.get(0) +
+            // "  callerCompLoc="
+            // + callerCompLoc + "  newCalleeCompLoc=" + newCalleeCompLoc);
+
+          } else {
+            CompositeLocation newCalleeCompLoc =
+                calculateCompositeLocationFromSubGlobalGraph(mdCallee, calleeParamFlowNode);
+            if (newCalleeCompLoc != null) {
+              calleeGlobalGraph.addMapLocationToInferCompositeLocation(calleeParamLocTuple.get(0),
+                  newCalleeCompLoc);
+              calleeParamFlowNode.setCompositeLocation(newCalleeCompLoc);
+            }
+          }
+
+          // System.out.println("-----------------calleeParamFlowNode="
+          // + calleeParamFlowNode.getCompositeLocation());
+
+          // }
+
+        }
+      }
+
+    }
+
+  }
+
+  private CompositeLocation calculateCompositeLocationFromSubGlobalGraph(MethodDescriptor md,
+      FlowNode paramNode) {
+
+    // System.out.println("#############################################################");
+    // System.out.println("calculateCompositeLocationFromSubGlobalGraph=" + paramNode);
+
+    GlobalFlowGraph subGlobalFlowGraph = getSubGlobalFlowGraph(md);
+    NTuple<Location> paramLocTuple = translateToLocTuple(md, paramNode.getDescTuple());
+    GlobalFlowNode paramGlobalNode = subGlobalFlowGraph.getFlowNode(paramLocTuple);
+
+    List<NTuple<Location>> prefixList = calculatePrefixList(subGlobalFlowGraph, paramGlobalNode);
+
+    Location prefixLoc = paramLocTuple.get(0);
+
+    Set<GlobalFlowNode> reachableNodeSet =
+        subGlobalFlowGraph.getReachableNodeSetByPrefix(paramGlobalNode.getLocTuple().get(0));
+    // Set<GlobalFlowNode> reachNodeSet = globalFlowGraph.getReachableNodeSetFrom(node);
+
+    // System.out.println("node=" + node + "    prefixList=" + prefixList);
+
+    for (int i = 0; i < prefixList.size(); i++) {
+      NTuple<Location> curPrefix = prefixList.get(i);
+      Set<NTuple<Location>> reachableCommonPrefixSet = new HashSet<NTuple<Location>>();
+
+      for (Iterator iterator2 = reachableNodeSet.iterator(); iterator2.hasNext();) {
+        GlobalFlowNode reachNode = (GlobalFlowNode) iterator2.next();
+        if (reachNode.getLocTuple().startsWith(curPrefix)) {
+          reachableCommonPrefixSet.add(reachNode.getLocTuple());
+        }
+      }
+      // System.out.println("reachableCommonPrefixSet=" + reachableCommonPrefixSet);
+
+      if (!reachableCommonPrefixSet.isEmpty()) {
+
+        MethodDescriptor curPrefixFirstElementMethodDesc =
+            (MethodDescriptor) curPrefix.get(0).getDescriptor();
+
+        MethodDescriptor nodePrefixLocFirstElementMethodDesc =
+            (MethodDescriptor) prefixLoc.getDescriptor();
+
+        // System.out.println("curPrefixFirstElementMethodDesc=" +
+        // curPrefixFirstElementMethodDesc);
+        // System.out.println("nodePrefixLocFirstElementMethodDesc="
+        // + nodePrefixLocFirstElementMethodDesc);
+
+        if (curPrefixFirstElementMethodDesc.equals(nodePrefixLocFirstElementMethodDesc)
+            || isTransitivelyCalledFrom(nodePrefixLocFirstElementMethodDesc,
+                curPrefixFirstElementMethodDesc)) {
+
+          // TODO
+          // if (!node.getLocTuple().startsWith(curPrefix.get(0))) {
+
+          Location curPrefixLocalLoc = curPrefix.get(0);
+          if (subGlobalFlowGraph.mapLocationToInferCompositeLocation.containsKey(curPrefixLocalLoc)) {
+            // in this case, the local variable of the current prefix has already got a composite
+            // location
+            // so we just ignore the current composite location.
+
+            // System.out.println("HERE WE DO NOT ASSIGN A COMPOSITE LOCATION TO =" + node
+            // + " DUE TO " + curPrefix);
+            return null;
+          }
+
+          if (!needToGenerateCompositeLocation(paramGlobalNode, curPrefix)) {
+            // System.out.println("NO NEED TO GENERATE COMP LOC to " + paramGlobalNode
+            // + " with prefix=" + curPrefix);
+            return null;
+          }
+
+          Location targetLocalLoc = paramGlobalNode.getLocTuple().get(0);
+          CompositeLocation newCompLoc = generateCompositeLocation(curPrefix);
+          // System.out.println("NEED TO ASSIGN COMP LOC TO " + paramGlobalNode + " with prefix="
+          // + curPrefix);
+          // System.out.println("-targetLocalLoc=" + targetLocalLoc + "   - newCompLoc=" +
+          // newCompLoc);
+
+          // makes sure that a newly generated location appears in the hierarchy graph
+          for (int compIdx = 0; compIdx < newCompLoc.getSize(); compIdx++) {
+            Location curLoc = newCompLoc.get(compIdx);
+            getHierarchyGraph(curLoc.getDescriptor()).getHNode(curLoc.getLocDescriptor());
+          }
+
+          subGlobalFlowGraph.addMapLocationToInferCompositeLocation(targetLocalLoc, newCompLoc);
+
+          return newCompLoc;
+
         }
 
       }
+
+    }
+    return null;
+  }
+
+  private int getParamIdx(CompositeLocation compLoc,
+      Map<Integer, NTuple<Descriptor>> mapIdxToArgTuple) {
+
+    // if the composite location is started with the argument descriptor
+    // return the argument's index. o.t. return -1
+
+    Set<Integer> keySet = mapIdxToArgTuple.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Integer key = (Integer) iterator.next();
+      NTuple<Descriptor> argTuple = mapIdxToArgTuple.get(key);
+      if (argTuple.size() > 0 && translateToDescTuple(compLoc.getTuple()).startsWith(argTuple)) {
+        // System.out.println("compLoc.getTuple=" + compLoc + " is started with " + argTuple);
+        return key.intValue();
+      }
+    }
+
+    return -1;
+  }
+
+  private boolean isPrimitiveType(NTuple<Descriptor> argTuple) {
+
+    Descriptor lastDesc = argTuple.get(argTuple.size() - 1);
+
+    if (lastDesc instanceof FieldDescriptor) {
+      return ((FieldDescriptor) lastDesc).getType().isPrimitive();
+    } else if (lastDesc instanceof VarDescriptor) {
+      return ((VarDescriptor) lastDesc).getType().isPrimitive();
+    } else if (lastDesc instanceof InterDescriptor) {
+      return true;
+    }
+
+    return false;
+  }
+
+  private CompositeLocation translateCompositeLocationToCallee(CompositeLocation callerCompLoc,
+      NTuple<Location> baseLocTuple, MethodDescriptor mdCallee) {
+
+    CompositeLocation newCalleeCompLoc = new CompositeLocation();
+
+    Location calleeThisLoc = new Location(mdCallee, mdCallee.getThis());
+    newCalleeCompLoc.addLocation(calleeThisLoc);
+
+    // remove the base tuple from the caller
+    // ex; In the method invoation foo.bar.methodA(), the callee will have the composite location
+    // ,which is relative to the 'this' variable, <THIS,...>
+    for (int i = baseLocTuple.size(); i < callerCompLoc.getSize(); i++) {
+      newCalleeCompLoc.addLocation(callerCompLoc.get(i));
+    }
+
+    return newCalleeCompLoc;
+
+  }
+
+  private void calculateGlobalValueFlowCompositeLocation() {
+
+    System.out.println("SSJAVA: Calculate composite locations in the global value flow graph");
+    MethodDescriptor methodDescEventLoop = ssjava.getMethodContainingSSJavaLoop();
+    GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(methodDescEventLoop);
+
+    Set<Location> calculatedPrefixSet = new HashSet<Location>();
+
+    Set<GlobalFlowNode> nodeSet = globalFlowGraph.getNodeSet();
+
+    next: for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+      GlobalFlowNode node = (GlobalFlowNode) iterator.next();
+
+      Location prefixLoc = node.getLocTuple().get(0);
+
+      if (calculatedPrefixSet.contains(prefixLoc)) {
+        // the prefix loc has been already assigned to a composite location
+        continue;
+      }
+
+      calculatedPrefixSet.add(prefixLoc);
+
+      // Set<GlobalFlowNode> incomingNodeSet = globalFlowGraph.getIncomingNodeSet(node);
+      List<NTuple<Location>> prefixList = calculatePrefixList(globalFlowGraph, node);
+
+      Set<GlobalFlowNode> reachableNodeSet =
+          globalFlowGraph.getReachableNodeSetByPrefix(node.getLocTuple().get(0));
+      // Set<GlobalFlowNode> reachNodeSet = globalFlowGraph.getReachableNodeSetFrom(node);
+
+      // System.out.println("node=" + node + "    prefixList=" + prefixList);
+      // System.out.println("---prefixList=" + prefixList);
+
+      nextprefix: for (int i = 0; i < prefixList.size(); i++) {
+        NTuple<Location> curPrefix = prefixList.get(i);
+        // System.out.println("---curPrefix=" + curPrefix);
+        Set<NTuple<Location>> reachableCommonPrefixSet = new HashSet<NTuple<Location>>();
+
+        for (Iterator iterator2 = reachableNodeSet.iterator(); iterator2.hasNext();) {
+          GlobalFlowNode reachNode = (GlobalFlowNode) iterator2.next();
+          if (reachNode.getLocTuple().startsWith(curPrefix)) {
+            reachableCommonPrefixSet.add(reachNode.getLocTuple());
+          }
+        }
+        // System.out.println("reachableCommonPrefixSet=" + reachableCommonPrefixSet);
+
+        if (!reachableCommonPrefixSet.isEmpty()) {
+
+          MethodDescriptor curPrefixFirstElementMethodDesc =
+              (MethodDescriptor) curPrefix.get(0).getDescriptor();
+
+          MethodDescriptor nodePrefixLocFirstElementMethodDesc =
+              (MethodDescriptor) prefixLoc.getDescriptor();
+
+          // System.out.println("curPrefixFirstElementMethodDesc=" +
+          // curPrefixFirstElementMethodDesc);
+          // System.out.println("nodePrefixLocFirstElementMethodDesc="
+          // + nodePrefixLocFirstElementMethodDesc);
+
+          if (curPrefixFirstElementMethodDesc.equals(nodePrefixLocFirstElementMethodDesc)
+              || isTransitivelyCalledFrom(nodePrefixLocFirstElementMethodDesc,
+                  curPrefixFirstElementMethodDesc)) {
+
+            // TODO
+            // if (!node.getLocTuple().startsWith(curPrefix.get(0))) {
+
+            Location curPrefixLocalLoc = curPrefix.get(0);
+            if (globalFlowGraph.mapLocationToInferCompositeLocation.containsKey(curPrefixLocalLoc)) {
+              // in this case, the local variable of the current prefix has already got a composite
+              // location
+              // so we just ignore the current composite location.
+
+              // System.out.println("HERE WE DO NOT ASSIGN A COMPOSITE LOCATION TO =" + node
+              // + " DUE TO " + curPrefix);
+
+              continue next;
+            }
+
+            if (!needToGenerateCompositeLocation(node, curPrefix)) {
+              // System.out.println("NO NEED TO GENERATE COMP LOC to " + node + " with prefix="
+              // + curPrefix);
+              // System.out.println("prefixList=" + prefixList);
+              // System.out.println("reachableNodeSet=" + reachableNodeSet);
+              continue nextprefix;
+            }
+
+            Location targetLocalLoc = node.getLocTuple().get(0);
+            CompositeLocation newCompLoc = generateCompositeLocation(curPrefix);
+            // System.out.println("NEED TO ASSIGN COMP LOC TO " + node + " with prefix=" +
+            // curPrefix);
+            // System.out.println("-targetLocalLoc=" + targetLocalLoc + "   - newCompLoc="
+            // + newCompLoc);
+            globalFlowGraph.addMapLocationToInferCompositeLocation(targetLocalLoc, newCompLoc);
+            // }
+
+            continue next;
+            // }
+
+          }
+
+        }
+
+      }
+
+    }
+  }
+
+  private boolean checkFlowNodeReturnThisField(MethodDescriptor md) {
+
+    MethodDescriptor methodDescEventLoop = ssjava.getMethodContainingSSJavaLoop();
+    GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(methodDescEventLoop);
+
+    FlowGraph flowGraph = getFlowGraph(md);
+
+    ClassDescriptor enclosingDesc = getClassTypeDescriptor(md.getThis());
+    if (enclosingDesc == null) {
+      return false;
+    }
+
+    int count = 0;
+    Set<FlowNode> returnNodeSet = flowGraph.getReturnNodeSet();
+    Set<GlobalFlowNode> globalReturnNodeSet = new HashSet<GlobalFlowNode>();
+    for (Iterator iterator = returnNodeSet.iterator(); iterator.hasNext();) {
+      FlowNode flowNode = (FlowNode) iterator.next();
+      NTuple<Location> locTuple = translateToLocTuple(md, flowNode.getDescTuple());
+      GlobalFlowNode globalReturnNode = globalFlowGraph.getFlowNode(locTuple);
+      globalReturnNodeSet.add(globalReturnNode);
+
+      List<NTuple<Location>> prefixList = calculatePrefixList(globalFlowGraph, globalReturnNode);
+      for (int i = 0; i < prefixList.size(); i++) {
+        NTuple<Location> curPrefix = prefixList.get(i);
+        ClassDescriptor cd =
+            getClassTypeDescriptor(curPrefix.get(curPrefix.size() - 1).getLocDescriptor());
+        if (cd != null && cd.equals(enclosingDesc)) {
+          count++;
+          break;
+        }
+      }
+
+    }
+
+    if (count == returnNodeSet.size()) {
+      // in this case, all return nodes in the method returns values coming from a location that
+      // starts with "this"
+
+      // System.out.println("$$$SET RETURN LOC TRUE=" + md);
+      mapMethodDescriptorToCompositeReturnCase.put(md, Boolean.TRUE);
+
+      // NameDescriptor returnLocDesc = new NameDescriptor("RLOC" + (locSeed++));
+      // NTuple<Descriptor> rDescTuple = new NTuple<Descriptor>();
+      // rDescTuple.add(md.getThis());
+      // rDescTuple.add(returnLocDesc);
+      //
+      // for (Iterator iterator = returnNodeSet.iterator(); iterator.hasNext();) {
+      // FlowNode rnode = (FlowNode) iterator.next();
+      // flowGraph.addValueFlowEdge(rnode.getDescTuple(), rDescTuple);
+      // }
+      //
+      // getMethodSummary(md).setRETURNLoc(new CompositeLocation(translateToLocTuple(md,
+      // rDescTuple)));
+
+    } else {
+      mapMethodDescriptorToCompositeReturnCase.put(md, Boolean.FALSE);
+    }
+
+    return mapMethodDescriptorToCompositeReturnCase.get(md).booleanValue();
+
+  }
+
+  private boolean needToGenerateCompositeLocation(GlobalFlowNode node, NTuple<Location> curPrefix) {
+    // return true if there is a path between a node to which we want to give a composite location
+    // and nodes which start with curPrefix
+
+    // System.out.println("---needToGenerateCompositeLocation curPrefix=" + curPrefix);
+
+    Location targetLocalLoc = node.getLocTuple().get(0);
+
+    MethodDescriptor md = (MethodDescriptor) targetLocalLoc.getDescriptor();
+    FlowGraph flowGraph = getFlowGraph(md);
+
+    FlowNode flowNode = flowGraph.getFlowNode(node.getDescTuple());
+    Set<FlowNode> reachableSet = flowGraph.getReachFlowNodeSetFrom(flowNode);
+
+    Set<FlowNode> paramNodeSet = flowGraph.getParamFlowNodeSet();
+    for (Iterator iterator = paramNodeSet.iterator(); iterator.hasNext();) {
+      FlowNode paramFlowNode = (FlowNode) iterator.next();
+      if (curPrefix.startsWith(translateToLocTuple(md, paramFlowNode.getDescTuple()))) {
+        return true;
+      }
+    }
+
+    if (targetLocalLoc.getLocDescriptor() instanceof InterDescriptor) {
+      Pair<MethodInvokeNode, Integer> pair =
+          ((InterDescriptor) targetLocalLoc.getLocDescriptor()).getMethodArgIdxPair();
+
+      if (pair != null) {
+        // System.out.println("$$$TARGETLOCALLOC HOLDER=" + targetLocalLoc);
+
+        MethodInvokeNode min = pair.getFirst();
+        Integer paramIdx = pair.getSecond();
+        MethodDescriptor mdCallee = min.getMethod();
+
+        FlowNode paramNode = getFlowGraph(mdCallee).getParamFlowNode(paramIdx);
+        if (checkNodeReachToReturnNode(mdCallee, paramNode)) {
+          return true;
+        }
+
+      }
+
+    }
+
+    GlobalFlowGraph subGlobalFlowGraph = getSubGlobalFlowGraph(md);
+    Set<GlobalFlowNode> subGlobalReachableSet = subGlobalFlowGraph.getReachableNodeSetFrom(node);
+
+    if (!md.isStatic()) {
+      ClassDescriptor currentMethodThisType = getClassTypeDescriptor(md.getThis());
+      for (int i = 0; i < curPrefix.size(); i++) {
+        ClassDescriptor prefixType = getClassTypeDescriptor(curPrefix.get(i).getLocDescriptor());
+        if (prefixType != null && prefixType.equals(currentMethodThisType)) {
+          // System.out.println("PREFIX TYPE MATCHES WITH=" + currentMethodThisType);
+
+          if (mapMethodDescriptorToCompositeReturnCase.containsKey(md)) {
+            boolean hasCompReturnLocWithThis =
+                mapMethodDescriptorToCompositeReturnCase.get(md).booleanValue();
+            if (hasCompReturnLocWithThis) {
+              if (checkNodeReachToReturnNode(md, flowNode)) {
+                return true;
+              }
+            }
+          }
+
+          for (Iterator iterator3 = subGlobalReachableSet.iterator(); iterator3.hasNext();) {
+            GlobalFlowNode subGlobalReachalbeNode = (GlobalFlowNode) iterator3.next();
+            if (subGlobalReachalbeNode.getLocTuple().get(0).getLocDescriptor().equals(md.getThis())) {
+              // System.out.println("PREFIX FOUND=" + subGlobalReachalbeNode);
+              return true;
+            }
+          }
+        }
+      }
+    }
+
+    Location lastLocationOfPrefix = curPrefix.get(curPrefix.size() - 1);
+    // check whether prefix appears in the list of parameters
+    Set<MethodInvokeNode> minSet = mapMethodDescToMethodInvokeNodeSet.get(md);
+    // System.out.println("$$$md=" + md + "   minSet=" + minSet);
+    if (minSet == null) {
+      return false;
+    }
+    found: for (Iterator iterator = minSet.iterator(); iterator.hasNext();) {
+      MethodInvokeNode min = (MethodInvokeNode) iterator.next();
+      Map<Integer, NTuple<Descriptor>> map = mapMethodInvokeNodeToArgIdxMap.get(min);
+      Set<Integer> keySet = map.keySet();
+      // System.out.println("min=" + min.printNode(0));
+
+      for (Iterator iterator2 = keySet.iterator(); iterator2.hasNext();) {
+        Integer argIdx = (Integer) iterator2.next();
+        NTuple<Descriptor> argTuple = map.get(argIdx);
+
+        if (!(!md.isStatic() && argIdx == 0)) {
+          // if the argTuple is empty, we don't need to do with anything(LITERAL CASE).
+          if (argTuple.size() > 0
+              && argTuple.get(argTuple.size() - 1).equals(lastLocationOfPrefix.getLocDescriptor())) {
+            NTuple<Location> locTuple =
+                translateToLocTuple(md, flowGraph.getParamFlowNode(argIdx).getDescTuple());
+            lastLocationOfPrefix = locTuple.get(0);
+            // System.out.println("ARG CASE=" + locTuple);
+            for (Iterator iterator3 = subGlobalReachableSet.iterator(); iterator3.hasNext();) {
+              GlobalFlowNode subGlobalReachalbeNode = (GlobalFlowNode) iterator3.next();
+              // NTuple<Location> locTuple = translateToLocTuple(md, reachalbeNode.getDescTuple());
+              NTuple<Location> globalReachlocTuple = subGlobalReachalbeNode.getLocTuple();
+              for (int i = 0; i < globalReachlocTuple.size(); i++) {
+                if (globalReachlocTuple.get(i).equals(lastLocationOfPrefix)) {
+                  // System.out.println("ARG  " + argTuple + "  IS MATCHED WITH="
+                  // + lastLocationOfPrefix);
+                  return true;
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+
+    return false;
+  }
+
+  private boolean checkNodeReachToReturnNode(MethodDescriptor md, FlowNode node) {
+
+    FlowGraph flowGraph = getFlowGraph(md);
+    Set<FlowNode> reachableSet = flowGraph.getReachFlowNodeSetFrom(node);
+    if (mapMethodDescriptorToCompositeReturnCase.containsKey(md)) {
+      boolean hasCompReturnLocWithThis =
+          mapMethodDescriptorToCompositeReturnCase.get(md).booleanValue();
+
+      if (hasCompReturnLocWithThis) {
+        for (Iterator iterator = flowGraph.getReturnNodeSet().iterator(); iterator.hasNext();) {
+          FlowNode returnFlowNode = (FlowNode) iterator.next();
+          if (reachableSet.contains(returnFlowNode)) {
+            return true;
+          }
+        }
+      }
+    }
+    return false;
+  }
+
+  private void assignCompositeLocation(CompositeLocation compLocPrefix, GlobalFlowNode node) {
+    CompositeLocation newCompLoc = compLocPrefix.clone();
+    NTuple<Location> locTuple = node.getLocTuple();
+    for (int i = 1; i < locTuple.size(); i++) {
+      newCompLoc.addLocation(locTuple.get(i));
+    }
+    node.setInferCompositeLocation(newCompLoc);
+  }
+
+  private List<NTuple<Location>> calculatePrefixList(GlobalFlowGraph graph, GlobalFlowNode node) {
+
+    // System.out.println("\n##### calculatePrefixList node=" + node);
+
+    Set<GlobalFlowNode> incomingNodeSetPrefix =
+        graph.getIncomingNodeSetByPrefix(node.getLocTuple().get(0));
+    // System.out.println("---incomingNodeSetPrefix=" + incomingNodeSetPrefix);
+
+    Set<GlobalFlowNode> reachableNodeSetPrefix =
+        graph.getReachableNodeSetByPrefix(node.getLocTuple().get(0));
+    // System.out.println("---reachableNodeSetPrefix=" + reachableNodeSetPrefix);
+
+    List<NTuple<Location>> prefixList = new ArrayList<NTuple<Location>>();
+
+    for (Iterator iterator = incomingNodeSetPrefix.iterator(); iterator.hasNext();) {
+      GlobalFlowNode inNode = (GlobalFlowNode) iterator.next();
+      NTuple<Location> inNodeTuple = inNode.getLocTuple();
+
+      if (inNodeTuple.get(0).getLocDescriptor() instanceof InterDescriptor
+          || inNodeTuple.get(0).getLocDescriptor().equals(GLOBALDESC)) {
+        continue;
+      }
+
+      for (int i = 1; i < inNodeTuple.size(); i++) {
+        NTuple<Location> prefix = inNodeTuple.subList(0, i);
+        if (!prefixList.contains(prefix)) {
+          prefixList.add(prefix);
+        }
+      }
+    }
+
+    Collections.sort(prefixList, new Comparator<NTuple<Location>>() {
+      public int compare(NTuple<Location> arg0, NTuple<Location> arg1) {
+        int s0 = arg0.size();
+        int s1 = arg1.size();
+        if (s0 > s1) {
+          return -1;
+        } else if (s0 == s1) {
+          return 0;
+        } else {
+          return 1;
+        }
+      }
+    });
+
+    return prefixList;
+
+  }
+
+  private CompositeLocation calculateCompositeLocationFromFlowGraph(MethodDescriptor md,
+      FlowNode node) {
+
+    // System.out.println("#############################################################");
+    // System.out.println("calculateCompositeLocationFromFlowGraph=" + node);
+
+    FlowGraph flowGraph = getFlowGraph(md);
+    // NTuple<Location> paramLocTuple = translateToLocTuple(md, paramNode.getDescTuple());
+    // GlobalFlowNode paramGlobalNode = subGlobalFlowGraph.getFlowNode(paramLocTuple);
+
+    List<NTuple<Location>> prefixList = calculatePrefixListFlowGraph(flowGraph, node);
+
+    // Set<GlobalFlowNode> reachableNodeSet =
+    // subGlobalFlowGraph.getReachableNodeSetByPrefix(paramGlobalNode.getLocTuple().get(0));
+    //
+    Set<FlowNode> reachableNodeSet =
+        flowGraph.getReachableSetFrom(node.getDescTuple().subList(0, 1));
+
+    // Set<GlobalFlowNode> reachNodeSet = globalFlowGraph.getReachableNodeSetFrom(node);
+
+    // System.out.println("node=" + node + "    prefixList=" + prefixList);
+
+    for (int i = 0; i < prefixList.size(); i++) {
+      NTuple<Location> curPrefix = prefixList.get(i);
+      Set<NTuple<Location>> reachableCommonPrefixSet = new HashSet<NTuple<Location>>();
+
+      for (Iterator iterator2 = reachableNodeSet.iterator(); iterator2.hasNext();) {
+        FlowNode reachNode = (FlowNode) iterator2.next();
+        NTuple<Location> reachLocTuple = translateToLocTuple(md, reachNode.getCurrentDescTuple());
+        if (reachLocTuple.startsWith(curPrefix)) {
+          reachableCommonPrefixSet.add(reachLocTuple);
+        }
+      }
+      // System.out.println("reachableCommonPrefixSet=" + reachableCommonPrefixSet);
+
+      if (!reachableCommonPrefixSet.isEmpty()) {
+
+        MethodDescriptor curPrefixFirstElementMethodDesc =
+            (MethodDescriptor) curPrefix.get(0).getDescriptor();
+
+        Location curPrefixLocalLoc = curPrefix.get(0);
+
+        Location targetLocalLoc = new Location(md, node.getDescTuple().get(0));
+        // Location targetLocalLoc = paramGlobalNode.getLocTuple().get(0);
+
+        CompositeLocation newCompLoc = generateCompositeLocation(curPrefix);
+        // System.out.println("NEED2ASSIGN COMP LOC TO " + node + " with prefix=" + curPrefix);
+        // System.out.println("-targetLocalLoc=" + targetLocalLoc + "   - newCompLoc=" +
+        // newCompLoc);
+
+        node.setCompositeLocation(newCompLoc);
+
+        return newCompLoc;
+
+      }
+
+    }
+    return null;
+  }
+
+  private List<NTuple<Location>> calculatePrefixListFlowGraph(FlowGraph graph, FlowNode node) {
+
+    // System.out.println("\n##### calculatePrefixList node=" + node);
+
+    MethodDescriptor md = graph.getMethodDescriptor();
+    Set<FlowNode> incomingNodeSetPrefix =
+        graph.getIncomingNodeSetByPrefix(node.getDescTuple().get(0));
+    // System.out.println("---incomingNodeSetPrefix=" + incomingNodeSetPrefix);
+
+    Set<FlowNode> reachableNodeSetPrefix =
+        graph.getReachableSetFrom(node.getDescTuple().subList(0, 1));
+    // System.out.println("---reachableNodeSetPrefix=" + reachableNodeSetPrefix);
+
+    List<NTuple<Location>> prefixList = new ArrayList<NTuple<Location>>();
+
+    for (Iterator iterator = incomingNodeSetPrefix.iterator(); iterator.hasNext();) {
+      FlowNode inNode = (FlowNode) iterator.next();
+      NTuple<Location> inNodeTuple = translateToLocTuple(md, inNode.getCurrentDescTuple());
+
+      // if (inNodeTuple.get(0).getLocDescriptor() instanceof InterDescriptor
+      // || inNodeTuple.get(0).getLocDescriptor().equals(GLOBALDESC)) {
+      // continue;
+      // }
+
+      for (int i = 1; i < inNodeTuple.size(); i++) {
+        NTuple<Location> prefix = inNodeTuple.subList(0, i);
+        if (!prefixList.contains(prefix)) {
+          prefixList.add(prefix);
+        }
+      }
+    }
+
+    Collections.sort(prefixList, new Comparator<NTuple<Location>>() {
+      public int compare(NTuple<Location> arg0, NTuple<Location> arg1) {
+        int s0 = arg0.size();
+        int s1 = arg1.size();
+        if (s0 > s1) {
+          return -1;
+        } else if (s0 == s1) {
+          return 0;
+        } else {
+          return 1;
+        }
+      }
+    });
+
+    return prefixList;
+
+  }
+
+  private GlobalFlowGraph constructSubGlobalFlowGraph(FlowGraph flowGraph) {
+
+    MethodDescriptor md = flowGraph.getMethodDescriptor();
+
+    GlobalFlowGraph globalGraph = getSubGlobalFlowGraph(md);
+
+    // Set<FlowNode> nodeSet = flowGraph.getNodeSet();
+    Set<FlowEdge> edgeSet = flowGraph.getEdgeSet();
+
+    for (Iterator iterator = edgeSet.iterator(); iterator.hasNext();) {
+
+      FlowEdge edge = (FlowEdge) iterator.next();
+      NTuple<Descriptor> srcDescTuple = edge.getInitTuple();
+      NTuple<Descriptor> dstDescTuple = edge.getEndTuple();
+
+      if (flowGraph.getFlowNode(srcDescTuple) instanceof FlowReturnNode
+          || flowGraph.getFlowNode(dstDescTuple) instanceof FlowReturnNode) {
+        continue;
+      }
+
+      // here only keep the first element(method location) of the descriptor
+      // tuple
+      NTuple<Location> srcLocTuple = translateToLocTuple(md, srcDescTuple);
+      NTuple<Location> dstLocTuple = translateToLocTuple(md, dstDescTuple);
+
+      globalGraph.addValueFlowEdge(srcLocTuple, dstLocTuple);
+
+    }
+
+    return globalGraph;
+  }
+
+  private NTuple<Location> translateToLocTuple(MethodDescriptor md, NTuple<Descriptor> descTuple) {
+
+    NTuple<Location> locTuple = new NTuple<Location>();
+
+    Descriptor enclosingDesc = md;
+    for (int i = 0; i < descTuple.size(); i++) {
+      Descriptor desc = descTuple.get(i);
+
+      Location loc = new Location(enclosingDesc, desc);
+      locTuple.add(loc);
+
+      if (desc instanceof VarDescriptor) {
+        enclosingDesc = ((VarDescriptor) desc).getType().getClassDesc();
+      } else if (desc instanceof FieldDescriptor) {
+        enclosingDesc = ((FieldDescriptor) desc).getType().getClassDesc();
+      } else {
+        enclosingDesc = desc;
+      }
+
+    }
+
+    return locTuple;
+
+  }
+
+  private void addValueFlowsFromCalleeSubGlobalFlowGraph(MethodDescriptor mdCaller) {
+
+    // the transformation for a call site propagates flows through parameters
+    // if the method is virtual, it also grab all relations from any possible
+    // callees
+
+    Set<MethodInvokeNode> setMethodInvokeNode = getMethodInvokeNodeSet(mdCaller);
+
+    for (Iterator iterator = setMethodInvokeNode.iterator(); iterator.hasNext();) {
+      MethodInvokeNode min = (MethodInvokeNode) iterator.next();
+      MethodDescriptor mdCallee = min.getMethod();
+      Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
+      if (mdCallee.isStatic()) {
+        setPossibleCallees.add(mdCallee);
+      } else {
+        Set<MethodDescriptor> calleeSet = ssjava.getCallGraph().getMethods(mdCallee);
+        // removes method descriptors that are not invoked by the caller
+        calleeSet.retainAll(mapMethodToCalleeSet.get(mdCaller));
+        setPossibleCallees.addAll(calleeSet);
+      }
+
+      for (Iterator iterator2 = setPossibleCallees.iterator(); iterator2.hasNext();) {
+        MethodDescriptor possibleMdCallee = (MethodDescriptor) iterator2.next();
+        propagateValueFlowsToCallerFromSubGlobalFlowGraph(min, mdCaller, possibleMdCallee);
+      }
+
+    }
+
+  }
+
+  private void propagateValueFlowsToCallerFromSubGlobalFlowGraph(MethodInvokeNode min,
+      MethodDescriptor mdCaller, MethodDescriptor possibleMdCallee) {
+
+    // System.out.println("---propagate from " + min.printNode(0) + " to caller=" + mdCaller);
+    FlowGraph calleeFlowGraph = getFlowGraph(possibleMdCallee);
+    Map<Integer, NTuple<Descriptor>> mapIdxToArg = mapMethodInvokeNodeToArgIdxMap.get(min);
+
+    // System.out.println("-----mapMethodInvokeNodeToArgIdxMap.get(min)="
+    // + mapMethodInvokeNodeToArgIdxMap.get(min));
+
+    Set<Integer> keySet = mapIdxToArg.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Integer idx = (Integer) iterator.next();
+      NTuple<Descriptor> argDescTuple = mapIdxToArg.get(idx);
+      if (argDescTuple.size() > 0) {
+        NTuple<Location> argLocTuple = translateToLocTuple(mdCaller, argDescTuple);
+        NTuple<Descriptor> paramDescTuple = calleeFlowGraph.getParamFlowNode(idx).getDescTuple();
+        NTuple<Location> paramLocTuple = translateToLocTuple(possibleMdCallee, paramDescTuple);
+        // System.out.println("-------paramDescTuple=" + paramDescTuple + "->argDescTuple="
+        // + argDescTuple);
+        addMapCallerArgToCalleeParam(min, argDescTuple, paramDescTuple);
+      }
+    }
+
+    // addValueFlowBetweenParametersToCaller(min, mdCaller, possibleMdCallee);
+
+    NTuple<Descriptor> baseTuple = mapMethodInvokeNodeToBaseTuple.get(min);
+    GlobalFlowGraph calleeSubGlobalGraph = getSubGlobalFlowGraph(possibleMdCallee);
+    Set<GlobalFlowNode> calleeNodeSet = calleeSubGlobalGraph.getNodeSet();
+    for (Iterator iterator = calleeNodeSet.iterator(); iterator.hasNext();) {
+      GlobalFlowNode calleeNode = (GlobalFlowNode) iterator.next();
+      addValueFlowFromCalleeNode(min, mdCaller, possibleMdCallee, calleeNode);
+    }
+
+    // System.out.println("$$$GLOBAL PC LOC ADD=" + mdCaller);
+    Set<NTuple<Location>> pcLocTupleSet = mapMethodInvokeNodeToPCLocTupleSet.get(min);
+    // System.out.println("---pcLocTupleSet=" + pcLocTupleSet);
+    GlobalFlowGraph callerSubGlobalGraph = getSubGlobalFlowGraph(mdCaller);
+    for (Iterator iterator = calleeNodeSet.iterator(); iterator.hasNext();) {
+      GlobalFlowNode calleeNode = (GlobalFlowNode) iterator.next();
+      if (calleeNode.isParamNodeWithIncomingFlows()) {
+        // System.out.println("calleeNode.getLocTuple()" + calleeNode.getLocTuple());
+        NTuple<Location> callerSrcNodeLocTuple =
+            translateToCallerLocTuple(min, possibleMdCallee, mdCaller, calleeNode.getLocTuple());
+        // System.out.println("---callerSrcNodeLocTuple=" + callerSrcNodeLocTuple);
+        if (callerSrcNodeLocTuple != null && callerSrcNodeLocTuple.size() > 0) {
+          for (Iterator iterator2 = pcLocTupleSet.iterator(); iterator2.hasNext();) {
+            NTuple<Location> pcLocTuple = (NTuple<Location>) iterator2.next();
+
+            callerSubGlobalGraph.addValueFlowEdge(pcLocTuple, callerSrcNodeLocTuple);
+          }
+        }
+      }
+
+    }
+
+  }
+
+  private void addValueFlowFromCalleeNode(MethodInvokeNode min, MethodDescriptor mdCaller,
+      MethodDescriptor mdCallee, GlobalFlowNode calleeSrcNode) {
+
+    GlobalFlowGraph calleeSubGlobalGraph = getSubGlobalFlowGraph(mdCallee);
+    GlobalFlowGraph callerSubGlobalGraph = getSubGlobalFlowGraph(mdCaller);
+
+    // System.out.println("$addValueFlowFromCalleeNode calleeSrcNode=" + calleeSrcNode);
+
+    NTuple<Location> callerSrcNodeLocTuple =
+        translateToCallerLocTuple(min, mdCallee, mdCaller, calleeSrcNode.getLocTuple());
+    // System.out.println("---callerSrcNodeLocTuple=" + callerSrcNodeLocTuple);
+
+    if (callerSrcNodeLocTuple != null && callerSrcNodeLocTuple.size() > 0) {
+
+      Set<GlobalFlowNode> outNodeSet = calleeSubGlobalGraph.getOutNodeSet(calleeSrcNode);
+
+      for (Iterator iterator = outNodeSet.iterator(); iterator.hasNext();) {
+        GlobalFlowNode outNode = (GlobalFlowNode) iterator.next();
+        NTuple<Location> callerDstNodeLocTuple =
+            translateToCallerLocTuple(min, mdCallee, mdCaller, outNode.getLocTuple());
+        // System.out.println("outNode=" + outNode + "   callerDstNodeLocTuple="
+        // + callerDstNodeLocTuple);
+        if (callerSrcNodeLocTuple != null && callerDstNodeLocTuple != null
+            && callerSrcNodeLocTuple.size() > 0 && callerDstNodeLocTuple.size() > 0) {
+          callerSubGlobalGraph.addValueFlowEdge(callerSrcNodeLocTuple, callerDstNodeLocTuple);
+        }
+      }
+    }
+
+  }
+
+  private NTuple<Location> translateToCallerLocTuple(MethodInvokeNode min,
+      MethodDescriptor mdCallee, MethodDescriptor mdCaller, NTuple<Location> nodeLocTuple) {
+    // this method will return the same nodeLocTuple if the corresponding argument is literal
+    // value.
+
+    // System.out.println("translateToCallerLocTuple=" + nodeLocTuple);
+
+    FlowGraph calleeFlowGraph = getFlowGraph(mdCallee);
+    NTuple<Descriptor> nodeDescTuple = translateToDescTuple(nodeLocTuple);
+    if (calleeFlowGraph.isParameter(nodeDescTuple)) {
+      int paramIdx = calleeFlowGraph.getParamIdx(nodeDescTuple);
+      NTuple<Descriptor> argDescTuple = mapMethodInvokeNodeToArgIdxMap.get(min).get(paramIdx);
+
+      // if (isPrimitive(nodeLocTuple.get(0).getLocDescriptor())) {
+      // // the type of argument is primitive.
+      // return nodeLocTuple.clone();
+      // }
+      // System.out.println("paramIdx=" + paramIdx + "  argDescTuple=" + argDescTuple + " from min="
+      // + min.printNode(0));
+      NTuple<Location> argLocTuple = translateToLocTuple(mdCaller, argDescTuple);
+
+      NTuple<Location> callerLocTuple = new NTuple<Location>();
+
+      callerLocTuple.addAll(argLocTuple);
+      for (int i = 1; i < nodeLocTuple.size(); i++) {
+        callerLocTuple.add(nodeLocTuple.get(i));
+      }
+      return callerLocTuple;
+    } else {
+      return nodeLocTuple.clone();
+    }
+
+  }
+
+  public static boolean isPrimitive(Descriptor desc) {
+
+    if (desc instanceof FieldDescriptor) {
+      return ((FieldDescriptor) desc).getType().isPrimitive();
+    } else if (desc instanceof VarDescriptor) {
+      return ((VarDescriptor) desc).getType().isPrimitive();
+    } else if (desc instanceof InterDescriptor) {
+      return true;
+    }
+
+    return false;
+  }
+
+  public static boolean isReference(Descriptor desc) {
+
+    if (desc instanceof FieldDescriptor) {
+
+      TypeDescriptor type = ((FieldDescriptor) desc).getType();
+      if (type.isArray()) {
+        return !type.isPrimitive();
+      } else {
+        return type.isPtr();
+      }
+
+    } else if (desc instanceof VarDescriptor) {
+      TypeDescriptor type = ((VarDescriptor) desc).getType();
+      if (type.isArray()) {
+        return !type.isPrimitive();
+      } else {
+        return type.isPtr();
+      }
+    }
+
+    return false;
+  }
+
+  private NTuple<Descriptor> translateToDescTuple(NTuple<Location> locTuple) {
+
+    NTuple<Descriptor> descTuple = new NTuple<Descriptor>();
+    for (int i = 0; i < locTuple.size(); i++) {
+      descTuple.add(locTuple.get(i).getLocDescriptor());
+    }
+    return descTuple;
+
+  }
+
+  public LocationSummary getLocationSummary(Descriptor d) {
+    if (!mapDescToLocationSummary.containsKey(d)) {
+      if (d instanceof MethodDescriptor) {
+        mapDescToLocationSummary.put(d, new MethodSummary((MethodDescriptor) d));
+      } else if (d instanceof ClassDescriptor) {
+        mapDescToLocationSummary.put(d, new FieldSummary());
+      }
+    }
+    return mapDescToLocationSummary.get(d);
+  }
+
+  private void generateMethodSummary() {
+
+    Set<MethodDescriptor> keySet = md2lattice.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+
+      System.out.println("\nSSJAVA: generate method summary: " + md);
+
+      FlowGraph flowGraph = getFlowGraph(md);
+      if (flowGraph == null) {
+        continue;
+      }
+      MethodSummary methodSummary = getMethodSummary(md);
+
+      HierarchyGraph scGraph = getSkeletonCombinationHierarchyGraph(md);
+
+      // set the 'this' reference location
+      if (!md.isStatic()) {
+        // System.out.println("setThisLocName=" + scGraph.getHNode(md.getThis()).getName());
+        methodSummary.setThisLocName(scGraph.getHNode(md.getThis()).getName());
+      }
+
+      // set the 'global' reference location if needed
+      if (methodSummary.hasGlobalAccess()) {
+        methodSummary.setGlobalLocName(scGraph.getHNode(GLOBALDESC).getName());
+      }
+
+      // construct a parameter mapping that maps a parameter descriptor to an
+      // inferred composite location
+      for (int paramIdx = 0; paramIdx < flowGraph.getNumParameters(); paramIdx++) {
+        FlowNode flowNode = flowGraph.getParamFlowNode(paramIdx);
+        CompositeLocation inferredCompLoc =
+            updateCompositeLocation(flowNode.getCompositeLocation());
+        // System.out.println("-paramIdx=" + paramIdx + "   infer=" + inferredCompLoc + " original="
+        // + flowNode.getCompositeLocation());
+
+        Descriptor localVarDesc = flowNode.getDescTuple().get(0);
+        methodSummary.addMapVarNameToInferCompLoc(localVarDesc, inferredCompLoc);
+        methodSummary.addMapParamIdxToInferLoc(paramIdx, inferredCompLoc);
+      }
+
+    }
+
+  }
+
+  private boolean hasOrderingRelation(NTuple<Location> locTuple1, NTuple<Location> locTuple2) {
+
+    int size = locTuple1.size() >= locTuple2.size() ? locTuple2.size() : locTuple1.size();
+
+    for (int idx = 0; idx < size; idx++) {
+      Location loc1 = locTuple1.get(idx);
+      Location loc2 = locTuple2.get(idx);
+
+      Descriptor desc1 = loc1.getDescriptor();
+      Descriptor desc2 = loc2.getDescriptor();
+
+      if (!desc1.equals(desc2)) {
+        throw new Error("Fail to compare " + locTuple1 + " and " + locTuple2);
+      }
+
+      Descriptor locDesc1 = loc1.getLocDescriptor();
+      Descriptor locDesc2 = loc2.getLocDescriptor();
+
+      HierarchyGraph hierarchyGraph = getHierarchyGraph(desc1);
+
+      HNode node1 = hierarchyGraph.getHNode(locDesc1);
+      HNode node2 = hierarchyGraph.getHNode(locDesc2);
+
+      // System.out.println("---node1=" + node1 + "  node2=" + node2);
+      // System.out.println("---hierarchyGraph.getIncomingNodeSet(node2)="
+      // + hierarchyGraph.getIncomingNodeSet(node2));
+
+      if (locDesc1.equals(locDesc2)) {
+        continue;
+      } else if (!hierarchyGraph.getIncomingNodeSet(node2).contains(node1)
+          && !hierarchyGraph.getIncomingNodeSet(node1).contains(node2)) {
+        return false;
+      } else {
+        return true;
+      }
+
+    }
+
+    return false;
+
+  }
+
+  private boolean isHigherThan(NTuple<Location> locTuple1, NTuple<Location> locTuple2) {
+
+    int size = locTuple1.size() >= locTuple2.size() ? locTuple2.size() : locTuple1.size();
+
+    for (int idx = 0; idx < size; idx++) {
+      Location loc1 = locTuple1.get(idx);
+      Location loc2 = locTuple2.get(idx);
+
+      Descriptor desc1 = loc1.getDescriptor();
+      Descriptor desc2 = loc2.getDescriptor();
+
+      if (!desc1.equals(desc2)) {
+        throw new Error("Fail to compare " + locTuple1 + " and " + locTuple2);
+      }
+
+      Descriptor locDesc1 = loc1.getLocDescriptor();
+      Descriptor locDesc2 = loc2.getLocDescriptor();
+
+      HierarchyGraph hierarchyGraph = getHierarchyGraph(desc1);
+
+      HNode node1 = hierarchyGraph.getHNode(locDesc1);
+      HNode node2 = hierarchyGraph.getHNode(locDesc2);
+
+      // System.out.println("---node1=" + node1 + "  node2=" + node2);
+      // System.out.println("---hierarchyGraph.getIncomingNodeSet(node2)="
+      // + hierarchyGraph.getIncomingNodeSet(node2));
+
+      if (locDesc1.equals(locDesc2)) {
+        continue;
+      } else if (hierarchyGraph.getIncomingNodeSet(node2).contains(node1)) {
+        return true;
+      } else {
+        return false;
+      }
+
+    }
+
+    return false;
+  }
+
+  private void debug_writeLattices() {
+
+    Set<Descriptor> keySet = mapDescriptorToSimpleLattice.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor key = (Descriptor) iterator.next();
+      SSJavaLattice<String> simpleLattice = mapDescriptorToSimpleLattice.get(key);
+      // HierarchyGraph simpleHierarchyGraph = getSimpleHierarchyGraph(key);
+      HierarchyGraph scHierarchyGraph = getSkeletonCombinationHierarchyGraph(key);
+      if (key instanceof ClassDescriptor) {
+        writeInferredLatticeDotFile((ClassDescriptor) key, simpleLattice, "_SIMPLE");
+      } else if (key instanceof MethodDescriptor) {
+        MethodDescriptor md = (MethodDescriptor) key;
+        writeInferredLatticeDotFile(md.getClassDesc(), md, simpleLattice, "_SIMPLE");
+      }
+
+      LocationSummary ls = getLocationSummary(key);
+      // System.out.println("####LOC SUMMARY=" + key + "\n" + ls.getMapHNodeNameToLocationName());
+    }
+
+    Set<ClassDescriptor> cdKeySet = cd2lattice.keySet();
+    for (Iterator iterator = cdKeySet.iterator(); iterator.hasNext();) {
+      ClassDescriptor cd = (ClassDescriptor) iterator.next();
+      // System.out.println("########cd=" + cd);
+      writeInferredLatticeDotFile((ClassDescriptor) cd, cd2lattice.get(cd), "");
+      COUNT += cd2lattice.get(cd).getKeySet().size();
+    }
+
+    Set<MethodDescriptor> mdKeySet = md2lattice.keySet();
+    for (Iterator iterator = mdKeySet.iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      writeInferredLatticeDotFile(md.getClassDesc(), md, md2lattice.get(md), "");
+      COUNT += md2lattice.get(md).getKeySet().size();
+    }
+    System.out.println("###COUNT=" + COUNT);
+
+    Set<Descriptor> descKeySet = desc2naiveLattice.keySet();
+    for (Iterator iterator = descKeySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      // System.out.println("########cd=" + cd);
+
+      ClassDescriptor cd_naive;
+      MethodDescriptor md_naive;
+      if (desc instanceof ClassDescriptor) {
+        cd_naive = (ClassDescriptor) desc;
+        md_naive = null;
+      } else {
+        md_naive = (MethodDescriptor) desc;
+        cd_naive = md_naive.getClassDesc();
+      }
+
+      writeInferredLatticeDotFile(cd_naive, md_naive, desc2naiveLattice.get(desc), "_naive");
+    }
+  }
+
+  private void buildLattice(Descriptor desc) {
+    // System.out.println("buildLattice=" + desc);
+    SSJavaLattice<String> simpleLattice = buildLattice.buildLattice(desc);
+
+    addMapDescToSimpleLattice(desc, simpleLattice);
+
+    if (desc instanceof ClassDescriptor) {
+      writeInferredLatticeDotFile((ClassDescriptor) desc, null, simpleLattice, "_SC");
+    } else {
+      MethodDescriptor md = (MethodDescriptor) desc;
+      writeInferredLatticeDotFile(md.getClassDesc(), md, simpleLattice, "_SC");
+    }
+
+    HierarchyGraph simpleHierarchyGraph = getSimpleHierarchyGraph(desc);
+
+    // System.out.println("\n## insertIntermediateNodesToStraightLine:"
+    // + simpleHierarchyGraph.getName());
+    SSJavaLattice<String> lattice =
+        buildLattice.insertIntermediateNodesToStraightLine(desc, simpleLattice);
+
+    if (lattice == null) {
+      return;
+    }
+    lattice.removeRedundantEdges();
+
+    LocationInference.numLocationsSInfer += lattice.getKeySet().size();
+
+    if (desc instanceof ClassDescriptor) {
+      // field lattice
+      cd2lattice.put((ClassDescriptor) desc, lattice);
+      // ssjava.writeLatticeDotFile((ClassDescriptor) desc, null, lattice);
+    } else if (desc instanceof MethodDescriptor) {
+      // method lattice
+      md2lattice.put((MethodDescriptor) desc, lattice);
+      MethodDescriptor md = (MethodDescriptor) desc;
+      ClassDescriptor cd = md.getClassDesc();
+      // ssjava.writeLatticeDotFile(cd, md, lattice);
+    }
+
+  }
+
+  // deprecated: it builds method/class lattices without considering class inheritance
+  private void buildLattice() {
+
+    Set<Descriptor> keySet = mapDescriptorToCombineSkeletonHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+
+      SSJavaLattice<String> simpleLattice = buildLattice.buildLattice(desc);
+
+      addMapDescToSimpleLattice(desc, simpleLattice);
+
+      HierarchyGraph simpleHierarchyGraph = getSimpleHierarchyGraph(desc);
+      System.out.println("\n## insertIntermediateNodesToStraightLine:"
+          + simpleHierarchyGraph.getName());
+      SSJavaLattice<String> lattice =
+          buildLattice.insertIntermediateNodesToStraightLine(desc, simpleLattice);
+      lattice.removeRedundantEdges();
+
+      LocationInference.numLocationsSInfer += lattice.getKeySet().size();
+
+      if (desc instanceof ClassDescriptor) {
+        // field lattice
+        cd2lattice.put((ClassDescriptor) desc, lattice);
+        // ssjava.writeLatticeDotFile((ClassDescriptor) desc, null, lattice);
+      } else if (desc instanceof MethodDescriptor) {
+        // method lattice
+        md2lattice.put((MethodDescriptor) desc, lattice);
+        MethodDescriptor md = (MethodDescriptor) desc;
+        ClassDescriptor cd = md.getClassDesc();
+        // ssjava.writeLatticeDotFile(cd, md, lattice);
+      }
+
+    }
+
+  }
+
+  private void buildLatticeInheritanceTree() {
+    // DFS the inheritance tree and propagates lattice nodes/edges from the parent to children
+    // Node<ClassDescriptor> rootNode = inheritanceTree.getRootNode();
+    DFSBuildLatticeInheritanceTree(rootClassDescriptor);
+  }
+
+  public Set<ClassDescriptor> getDirectSubClasses(ClassDescriptor parent) {
+
+    Set<ClassDescriptor> result = new HashSet<ClassDescriptor>();
+
+    Set<ClassDescriptor> children = tu.getDirectSubClasses(parent);
+    if (children == null) {
+      children = new HashSet<ClassDescriptor>();
+    }
+
+    for (Iterator iterator = children.iterator(); iterator.hasNext();) {
+      ClassDescriptor child = (ClassDescriptor) iterator.next();
+      if (toanalyze_classDescSet.contains(child)) {
+        result.add(child);
+      }
+    }
+
+    return result;
+  }
+
+  private void DFSBuildLatticeInheritanceTree(ClassDescriptor cd) {
+    // ClassDescriptor cd = node.getData();
+
+    ClassDescriptor parentClassDesc = cd.getSuperDesc();
+    if (parentClassDesc != null) {
+      Map<TripleItem, String> parentMap = buildLattice.getIntermediateLocMap(parentClassDesc);
+      buildLattice.setIntermediateLocMap(cd, parentMap);
+    }
+
+    buildLattice(cd);
+
+    for (Iterator iterator = cd.getMethods(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      if (toanalyze_methodDescList.contains(md)) {
+        MethodDescriptor parentMethodDesc = getParentMethodDesc(md.getClassDesc(), md);
+        if (parentMethodDesc != null) {
+          Map<TripleItem, String> parentMap = buildLattice.getIntermediateLocMap(parentMethodDesc);
+          Map<TripleItem, String> childMap = new HashMap<TripleItem, String>();
+          Set<TripleItem> keySet = parentMap.keySet();
+          for (Iterator iterator2 = keySet.iterator(); iterator2.hasNext();) {
+            TripleItem key = (TripleItem) iterator2.next();
+            childMap.put(key, parentMap.get(key));
+          }
+          buildLattice.setIntermediateLocMap(md, childMap);
+        }
+        buildLattice(md);
+      }
+    }
+
+    // traverse children
+    Set<ClassDescriptor> children = tu.getDirectSubClasses(cd);
+    if (children != null) {
+      for (Iterator iterator = children.iterator(); iterator.hasNext();) {
+        ClassDescriptor classDescriptor = (ClassDescriptor) iterator.next();
+        if (toanalyze_classDescSet.contains(classDescriptor)) {
+          DFSBuildLatticeInheritanceTree(classDescriptor);
+        } else {
+          if (classDescriptor.isAbstract()) {
+            DFSBuildLatticeInheritanceTree(classDescriptor);
+          }
+        }
+      }
+    }
+
+  }
+
+  public void addMapDescToSimpleLattice(Descriptor desc, SSJavaLattice<String> lattice) {
+    mapDescriptorToSimpleLattice.put(desc, lattice);
+  }
+
+  public SSJavaLattice<String> getSimpleLattice(Descriptor desc) {
+    return mapDescriptorToSimpleLattice.get(desc);
+  }
+
+  private void simplifyHierarchyGraph() {
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      // System.out.println("SSJAVA: remove redundant edges: " + desc);
+      HierarchyGraph simpleHierarchyGraph = getHierarchyGraph(desc).clone();
+      simpleHierarchyGraph.setName(desc + "_SIMPLE");
+      simpleHierarchyGraph.removeRedundantEdges();
+      mapDescriptorToSimpleHierarchyGraph.put(desc, simpleHierarchyGraph);
+    }
+  }
+
+  private void insertCombinationNodes() {
+    Set<Descriptor> keySet = mapDescriptorToSkeletonHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      System.out.println("\nSSJAVA: Inserting Combination Nodes:" + desc);
+      HierarchyGraph skeletonGraph = getSkeletonHierarchyGraph(desc);
+      HierarchyGraph skeletonGraphWithCombinationNode = skeletonGraph.clone();
+      skeletonGraphWithCombinationNode.setName(desc + "_SC");
+
+      HierarchyGraph simpleHierarchyGraph = getSimpleHierarchyGraph(desc);
+      skeletonGraphWithCombinationNode.insertCombinationNodesToGraph(simpleHierarchyGraph);
+      // skeletonGraphWithCombinationNode.insertCombinationNodesToGraph(simpleHierarchyGraph,
+      // skeletonGraph);
+      // skeletonGraphWithCombinationNode.simplifySkeletonCombinationHierarchyGraph();
+      skeletonGraphWithCombinationNode.removeRedundantEdges();
+      mapDescriptorToCombineSkeletonHierarchyGraph.put(desc, skeletonGraphWithCombinationNode);
+    }
+  }
+
+  private void constructSkeletonHierarchyGraph() {
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      System.out.println("SSJAVA: Constructing Skeleton Hierarchy Graph: " + desc);
+      HierarchyGraph simpleGraph = getSimpleHierarchyGraph(desc);
+      HierarchyGraph skeletonGraph = simpleGraph.generateSkeletonGraph();
+      skeletonGraph.setMapDescToHNode(simpleGraph.getMapDescToHNode());
+      skeletonGraph.setMapHNodeToDescSet(simpleGraph.getMapHNodeToDescSet());
+      skeletonGraph.simplifyHierarchyGraph(this);
+      mapDescriptorToSkeletonHierarchyGraph.put(desc, skeletonGraph);
+    }
+  }
+
+  private void recurUpAccumulateInheritanceDesc(Descriptor curDesc, Set<Descriptor> set) {
+
+    if (curDesc instanceof ClassDescriptor) {
+      ClassDescriptor cd = (ClassDescriptor) curDesc;
+      ClassDescriptor parentClassDesc = cd.getSuperDesc();
+      if (parentClassDesc != null && !parentClassDesc.equals(rootClassDescriptor)) {
+        set.add(parentClassDesc);
+        recurUpAccumulateInheritanceDesc(parentClassDesc, set);
+      }
+    } else {
+      MethodDescriptor md = (MethodDescriptor) curDesc;
+      ClassDescriptor cd = md.getClassDesc();
+
+      // traverse up
+      ClassDescriptor parentClassDesc = cd.getSuperDesc();
+      if (parentClassDesc != null && !parentClassDesc.equals(rootClassDescriptor)) {
+
+        Set<MethodDescriptor> methodDescSet =
+            parentClassDesc.getMethodTable().getSet(md.getSymbol());
+        for (Iterator iterator = methodDescSet.iterator(); iterator.hasNext();) {
+          MethodDescriptor parentMethodDesc = (MethodDescriptor) iterator.next();
+          if (parentMethodDesc.matches(md)) {
+            set.add(parentMethodDesc);
+            recurUpAccumulateInheritanceDesc(parentMethodDesc, set);
+          }
+        }
+      }
+
+    }
+
+  }
+
+  private void recurDownAccumulateInheritanceDesc(Descriptor curDesc, Set<Descriptor> set) {
+
+    if (curDesc instanceof ClassDescriptor) {
+      ClassDescriptor cd = (ClassDescriptor) curDesc;
+      ClassDescriptor parentClassDesc = cd.getSuperDesc();
+      Set<ClassDescriptor> directSubClasses = tu.getDirectSubClasses(cd);
+      for (Iterator iterator = directSubClasses.iterator(); iterator.hasNext();) {
+        ClassDescriptor child = (ClassDescriptor) iterator.next();
+        recurDownAccumulateInheritanceDesc(child, set);
+      }
+    } else {
+      MethodDescriptor md = (MethodDescriptor) curDesc;
+      ClassDescriptor cd = md.getClassDesc();
+
+      // traverse down
+      Set<ClassDescriptor> directSubClasses = tu.getDirectSubClasses(cd);
+      for (Iterator iterator = directSubClasses.iterator(); iterator.hasNext();) {
+        ClassDescriptor child = (ClassDescriptor) iterator.next();
+
+        Set<MethodDescriptor> methodDescSet = child.getMethodTable().getSet(md.getSymbol());
+        for (Iterator iterator2 = methodDescSet.iterator(); iterator2.hasNext();) {
+          MethodDescriptor childMethodDesc = (MethodDescriptor) iterator2.next();
+          if (childMethodDesc.matches(md)) {
+            set.add(childMethodDesc);
+            recurDownAccumulateInheritanceDesc(childMethodDesc, set);
+          }
+        }
+      }
+
+    }
+
+  }
+
+  private void accumulateInheritanceDesc(Descriptor curDesc, Set<Descriptor> set) {
+
+    recurUpAccumulateInheritanceDesc(curDesc, set);
+    recurDownAccumulateInheritanceDesc(curDesc, set);
+
+  }
+
+  public boolean isValidMergeInheritanceCheck(Descriptor desc, Set<HNode> mergeSet) {
+
+    // set up inheritance chain set...
+    Set<Descriptor> inheritanceDescSet = new HashSet<Descriptor>();
+    recurUpAccumulateInheritanceDesc(desc, inheritanceDescSet);
+
+    nextgraph: for (Iterator iterator = inheritanceDescSet.iterator(); iterator.hasNext();) {
+      Descriptor inheritDesc = (Descriptor) iterator.next();
+
+      if (!desc.equals(inheritDesc)) {
+        HierarchyGraph graph = getSkeletonCombinationHierarchyGraph(inheritDesc);
+
+        // first check whether this graph includes all elements of the merge set
+        for (Iterator iterator2 = mergeSet.iterator(); iterator2.hasNext();) {
+          HNode node = (HNode) iterator2.next();
+          if (!graph.contains(node)) {
+            continue nextgraph;
+          }
+        }
+
+        HNode firstNode = mergeSet.iterator().next();
+
+        Set<HNode> incomingNode = graph.getIncomingNodeSet(firstNode);
+        Set<HNode> outgoingNode = graph.getOutgoingNodeSet(firstNode);
+
+        for (Iterator iterator2 = mergeSet.iterator(); iterator2.hasNext();) {
+          HNode node = (HNode) iterator2.next();
+
+          if (!graph.getIncomingNodeSet(node).equals(incomingNode)
+              || !graph.getOutgoingNodeSet(node).equals(outgoingNode)) {
+            return false;
+          }
+
+        }
+      }
+
+    }
+
+    return true;
+  }
+
+  private void debug_writeHierarchyDotFiles() {
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      getHierarchyGraph(desc).writeGraph();
+    }
+
+  }
+
+  private void debug_writeSimpleHierarchyDotFiles() {
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      getHierarchyGraph(desc).writeGraph();
+      getSimpleHierarchyGraph(desc).writeGraph();
+      getSimpleHierarchyGraph(desc).writeGraph(true);
+    }
+
+  }
+
+  private void debug_writeSkeletonHierarchyDotFiles() {
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      getSkeletonHierarchyGraph(desc).writeGraph();
+    }
+
+  }
+
+  private void debug_writeSkeletonCombinationHierarchyDotFiles() {
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      getSkeletonCombinationHierarchyGraph(desc).writeGraph();
+    }
+
+  }
+
+  public HierarchyGraph getSimpleHierarchyGraph(Descriptor d) {
+    return mapDescriptorToSimpleHierarchyGraph.get(d);
+  }
+
+  private HierarchyGraph getSkeletonHierarchyGraph(Descriptor d) {
+    if (!mapDescriptorToSkeletonHierarchyGraph.containsKey(d)) {
+      mapDescriptorToSkeletonHierarchyGraph.put(d, new HierarchyGraph(d));
+    }
+    return mapDescriptorToSkeletonHierarchyGraph.get(d);
+  }
+
+  public HierarchyGraph getSkeletonCombinationHierarchyGraph(Descriptor d) {
+    if (!mapDescriptorToCombineSkeletonHierarchyGraph.containsKey(d)) {
+      mapDescriptorToCombineSkeletonHierarchyGraph.put(d, new HierarchyGraph(d));
+    }
+    return mapDescriptorToCombineSkeletonHierarchyGraph.get(d);
+  }
+
+  private void constructHierarchyGraph() {
+
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+      if (state.SSJAVADEBUG) {
+        HierarchyGraph hierarchyGraph = new HierarchyGraph(md);
+        System.out.println();
+        System.out.println("SSJAVA: Construcing the hierarchy graph from " + md);
+        constructHierarchyGraph(md, hierarchyGraph);
+        mapDescriptorToHierarchyGraph.put(md, hierarchyGraph);
+
+      }
+    }
+
+    setupToAnalyze();
+    while (!toAnalyzeIsEmpty()) {
+      ClassDescriptor cd = toAnalyzeNext();
+      HierarchyGraph graph = getHierarchyGraph(cd);
+      for (Iterator iter = cd.getFields(); iter.hasNext();) {
+        FieldDescriptor fieldDesc = (FieldDescriptor) iter.next();
+        if (!(fieldDesc.isStatic() && fieldDesc.isFinal())) {
+          graph.getHNode(fieldDesc);
+        }
+      }
+    }
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor key = (Descriptor) iterator.next();
+      HierarchyGraph graph = getHierarchyGraph(key);
+
+      Set<HNode> nodeToBeConnected = new HashSet<HNode>();
+      for (Iterator iterator2 = graph.getNodeSet().iterator(); iterator2.hasNext();) {
+        HNode node = (HNode) iterator2.next();
+        if (!node.isSkeleton() && !node.isCombinationNode()) {
+          if (graph.getIncomingNodeSet(node).size() == 0) {
+            nodeToBeConnected.add(node);
+          }
+        }
+      }
+
+      for (Iterator iterator2 = nodeToBeConnected.iterator(); iterator2.hasNext();) {
+        HNode node = (HNode) iterator2.next();
+        // System.out.println("NEED TO BE CONNECTED TO TOP=" + node);
+        graph.addEdge(graph.getHNode(TOPDESC), node);
+      }
+
+    }
+
+  }
+
+  private void constructHierarchyGraph2() {
+
+    // do fixed-point analysis
+
+    LinkedList<MethodDescriptor> descriptorListToAnalyze = ssjava.getSortedDescriptors();
+
+    // Collections.sort(descriptorListToAnalyze, new
+    // Comparator<MethodDescriptor>() {
+    // public int compare(MethodDescriptor o1, MethodDescriptor o2) {
+    // return o1.getSymbol().compareToIgnoreCase(o2.getSymbol());
+    // }
+    // });
+
+    // current descriptors to visit in fixed-point interprocedural analysis,
+    // prioritized by dependency in the call graph
+    methodDescriptorsToVisitStack.clear();
+
+    Set<MethodDescriptor> methodDescriptorToVistSet = new HashSet<MethodDescriptor>();
+    methodDescriptorToVistSet.addAll(descriptorListToAnalyze);
+
+    while (!descriptorListToAnalyze.isEmpty()) {
+      MethodDescriptor md = descriptorListToAnalyze.removeFirst();
+      methodDescriptorsToVisitStack.add(md);
+    }
+
+    // analyze scheduled methods until there are no more to visit
+    while (!methodDescriptorsToVisitStack.isEmpty()) {
+      // start to analyze leaf node
+      MethodDescriptor md = methodDescriptorsToVisitStack.pop();
+
+      HierarchyGraph hierarchyGraph = new HierarchyGraph(md);
+      // MethodSummary methodSummary = new MethodSummary(md);
+
+      // MethodLocationInfo methodInfo = new MethodLocationInfo(md);
+      // curMethodInfo = methodInfo;
+
+      System.out.println();
+      System.out.println("SSJAVA: Construcing the hierarchy graph from " + md);
+
+      constructHierarchyGraph(md, hierarchyGraph);
+
+      HierarchyGraph prevHierarchyGraph = getHierarchyGraph(md);
+      // MethodSummary prevMethodSummary = getMethodSummary(md);
+
+      if (!hierarchyGraph.equals(prevHierarchyGraph)) {
+
+        mapDescriptorToHierarchyGraph.put(md, hierarchyGraph);
+        // mapDescToLocationSummary.put(md, methodSummary);
+
+        // results for callee changed, so enqueue dependents caller for
+        // further analysis
+        Iterator<MethodDescriptor> depsItr = ssjava.getDependents(md).iterator();
+        while (depsItr.hasNext()) {
+          MethodDescriptor methodNext = depsItr.next();
+          if (!methodDescriptorsToVisitStack.contains(methodNext)
+              && methodDescriptorToVistSet.contains(methodNext)) {
+            methodDescriptorsToVisitStack.add(methodNext);
+          }
+        }
+
+      }
+
+    }
+
+    setupToAnalyze();
+    while (!toAnalyzeIsEmpty()) {
+      ClassDescriptor cd = toAnalyzeNext();
+      HierarchyGraph graph = getHierarchyGraph(cd);
+      for (Iterator iter = cd.getFields(); iter.hasNext();) {
+        FieldDescriptor fieldDesc = (FieldDescriptor) iter.next();
+        if (!(fieldDesc.isStatic() && fieldDesc.isFinal())) {
+          graph.getHNode(fieldDesc);
+        }
+      }
+    }
+
+    Set<Descriptor> keySet = mapDescriptorToHierarchyGraph.keySet();
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      Descriptor key = (Descriptor) iterator.next();
+      HierarchyGraph graph = getHierarchyGraph(key);
+
+      Set<HNode> nodeToBeConnected = new HashSet<HNode>();
+      for (Iterator iterator2 = graph.getNodeSet().iterator(); iterator2.hasNext();) {
+        HNode node = (HNode) iterator2.next();
+        if (!node.isSkeleton() && !node.isCombinationNode()) {
+          if (graph.getIncomingNodeSet(node).size() == 0) {
+            nodeToBeConnected.add(node);
+          }
+        }
+      }
+
+      for (Iterator iterator2 = nodeToBeConnected.iterator(); iterator2.hasNext();) {
+        HNode node = (HNode) iterator2.next();
+        // System.out.println("NEED TO BE CONNECTED TO TOP=" + node);
+        graph.addEdge(graph.getHNode(TOPDESC), node);
+      }
+
+    }
+
+  }
+
+  private HierarchyGraph getHierarchyGraph(Descriptor d) {
+    if (!mapDescriptorToHierarchyGraph.containsKey(d)) {
+      mapDescriptorToHierarchyGraph.put(d, new HierarchyGraph(d));
+    }
+    return mapDescriptorToHierarchyGraph.get(d);
+  }
+
+  private void constructHierarchyGraph(MethodDescriptor md, HierarchyGraph methodGraph) {
+
+    // visit each node of method flow graph
+    FlowGraph fg = getFlowGraph(md);
+    // Set<FlowNode> nodeSet = fg.getNodeSet();
+
+    Set<FlowEdge> edgeSet = fg.getEdgeSet();
+
+    Set<Descriptor> paramDescSet = fg.getMapParamDescToIdx().keySet();
+    for (Iterator iterator = paramDescSet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+      methodGraph.getHNode(desc).setSkeleton(true);
+    }
+
+    // for the method lattice, we need to look at the first element of
+    // NTuple<Descriptor>
+    boolean hasGlobalAccess = false;
+    // for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+    // FlowNode originalSrcNode = (FlowNode) iterator.next();
+    for (Iterator iterator = edgeSet.iterator(); iterator.hasNext();) {
+      FlowEdge edge = (FlowEdge) iterator.next();
+
+      FlowNode originalSrcNode = fg.getFlowNode(edge.getInitTuple());
+      Set<FlowNode> sourceNodeSet = new HashSet<FlowNode>();
+      if (originalSrcNode instanceof FlowReturnNode) {
+        FlowReturnNode rnode = (FlowReturnNode) originalSrcNode;
+        // System.out.println("rnode=" + rnode);
+        Set<NTuple<Descriptor>> tupleSet = rnode.getReturnTupleSet();
+        for (Iterator iterator2 = tupleSet.iterator(); iterator2.hasNext();) {
+          NTuple<Descriptor> nTuple = (NTuple<Descriptor>) iterator2.next();
+          sourceNodeSet.add(fg.getFlowNode(nTuple));
+          // System.out.println("&&&SOURCE fg.getFlowNode(nTuple)=" + fg.getFlowNode(nTuple));
+        }
+      } else {
+        sourceNodeSet.add(originalSrcNode);
+      }
+
+      // System.out.println("---sourceNodeSet=" + sourceNodeSet + "  from originalSrcNode="
+      // + originalSrcNode);
+
+      for (Iterator iterator3 = sourceNodeSet.iterator(); iterator3.hasNext();) {
+        FlowNode srcNode = (FlowNode) iterator3.next();
+
+        NTuple<Descriptor> srcNodeTuple = srcNode.getDescTuple();
+        Descriptor srcLocalDesc = srcNodeTuple.get(0);
+
+        if (srcLocalDesc instanceof InterDescriptor
+            && ((InterDescriptor) srcLocalDesc).getMethodArgIdxPair() != null) {
+
+          if (srcNode.getCompositeLocation() == null) {
+            continue;
+          }
+        }
+
+        // if the srcNode is started with the global descriptor
+        // need to set as a skeleton node
+        if (!hasGlobalAccess && srcNode.getDescTuple().startsWith(GLOBALDESC)) {
+          hasGlobalAccess = true;
+        }
+
+        // Set<FlowEdge> outEdgeSet = fg.getOutEdgeSet(originalSrcNode);
+        // for (Iterator iterator2 = outEdgeSet.iterator(); iterator2.hasNext();) {
+        // FlowEdge outEdge = (FlowEdge) iterator2.next();
+        // FlowNode originalDstNode = outEdge.getDst();
+        FlowNode originalDstNode = fg.getFlowNode(edge.getEndTuple());
+
+        Set<FlowNode> dstNodeSet = new HashSet<FlowNode>();
+        if (originalDstNode instanceof FlowReturnNode) {
+          FlowReturnNode rnode = (FlowReturnNode) originalDstNode;
+          // System.out.println("\n-returnNode=" + rnode);
+          Set<NTuple<Descriptor>> tupleSet = rnode.getReturnTupleSet();
+          for (Iterator iterator4 = tupleSet.iterator(); iterator4.hasNext();) {
+            NTuple<Descriptor> nTuple = (NTuple<Descriptor>) iterator4.next();
+            dstNodeSet.add(fg.getFlowNode(nTuple));
+            // System.out.println("&&&DST fg.getFlowNode(nTuple)=" + fg.getFlowNode(nTuple));
+          }
+        } else {
+          dstNodeSet.add(originalDstNode);
+        }
+        // System.out.println("---dstNodeSet=" + dstNodeSet);
+        for (Iterator iterator4 = dstNodeSet.iterator(); iterator4.hasNext();) {
+          FlowNode dstNode = (FlowNode) iterator4.next();
+
+          NTuple<Descriptor> dstNodeTuple = dstNode.getDescTuple();
+          Descriptor dstLocalDesc = dstNodeTuple.get(0);
+
+          if (dstLocalDesc instanceof InterDescriptor
+              && ((InterDescriptor) dstLocalDesc).getMethodArgIdxPair() != null) {
+            if (dstNode.getCompositeLocation() == null) {
+              // System.out.println("%%%%%%%%%%%%%SKIP=" + dstNode);
+              continue;
+            }
+          }
+
+          // if (outEdge.getInitTuple().equals(srcNodeTuple)
+          // && outEdge.getEndTuple().equals(dstNodeTuple)) {
+
+          NTuple<Descriptor> srcCurTuple = srcNode.getCurrentDescTuple();
+          NTuple<Descriptor> dstCurTuple = dstNode.getCurrentDescTuple();
+
+          // //////////////////////////
+          // inheritance check
+          if (mapMethodDescToHighestOverriddenMethodDesc.containsKey(md)) {
+
+            MethodDescriptor highestOverriddenMethodDesc =
+                mapMethodDescToHighestOverriddenMethodDesc.get(md);
+
+            if (srcCurTuple.get(srcCurTuple.size() - 1).getSymbol().startsWith(PCLOC)) {
+            }
+
+          }
+          // //////////////////////////
+
+          // System.out.println("-srcCurTuple=" + srcCurTuple + "  dstCurTuple=" + dstCurTuple
+          // + "  srcNode=" + srcNode + "   dstNode=" + dstNode);
+
+          // srcCurTuple = translateBaseTuple(srcNode, srcCurTuple);
+          // dstCurTuple = translateBaseTuple(dstNode, dstCurTuple);
+
+          if ((srcCurTuple.size() > 1 && dstCurTuple.size() > 1)
+              && srcCurTuple.get(0).equals(dstCurTuple.get(0))) {
+
+            // value flows between fields
+            Descriptor desc = srcCurTuple.get(0);
+            ClassDescriptor classDesc;
+
+            if (desc.equals(GLOBALDESC)) {
+              classDesc = md.getClassDesc();
+            } else {
+              VarDescriptor varDesc = (VarDescriptor) srcCurTuple.get(0);
+              classDesc = varDesc.getType().getClassDesc();
+            }
+            extractFlowsBetweenFields(classDesc, srcNode, dstNode, 1);
+
+          } else if ((srcCurTuple.size() == 1 && dstCurTuple.size() == 1)
+              || ((srcCurTuple.size() > 1 || dstCurTuple.size() > 1) && !srcCurTuple.get(0).equals(
+                  dstCurTuple.get(0)))) {
+
+            // value flow between a primitive local var - a primitive local var or local var -
+            // field
+
+            Descriptor srcDesc = srcCurTuple.get(0);
+            Descriptor dstDesc = dstCurTuple.get(0);
+
+            methodGraph.addEdge(srcDesc, dstDesc);
+
+            if (fg.isParamDesc(srcDesc)) {
+              methodGraph.setParamHNode(srcDesc);
+            }
+            if (fg.isParamDesc(dstDesc)) {
+              methodGraph.setParamHNode(dstDesc);
+            }
+
+          }
+
+          // }
+          // }
+
+        }
+
+      }
+
+    }
+
+    // If the method accesses static fields
+    // set hasGloabalAccess true in the method summary.
+    if (hasGlobalAccess) {
+      getMethodSummary(md).setHasGlobalAccess();
+    }
+    methodGraph.getHNode(GLOBALDESC).setSkeleton(true);
+
+    if (ssjava.getMethodContainingSSJavaLoop().equals(md)) {
+      // if the current method contains the event loop
+      // we need to set all nodes of the hierarchy graph as a skeleton node
+      Set<HNode> hnodeSet = methodGraph.getNodeSet();
+      for (Iterator iterator = hnodeSet.iterator(); iterator.hasNext();) {
+        HNode hnode = (HNode) iterator.next();
+        hnode.setSkeleton(true);
+      }
+    }
+
+  }
+
+  private NTuple<Descriptor> translateBaseTuple(FlowNode flowNode, NTuple<Descriptor> inTuple) {
+
+    if (flowNode.getBaseTuple() != null) {
+
+      NTuple<Descriptor> translatedTuple = new NTuple<Descriptor>();
+
+      NTuple<Descriptor> baseTuple = flowNode.getBaseTuple();
+
+      for (int i = 0; i < baseTuple.size(); i++) {
+        translatedTuple.add(baseTuple.get(i));
+      }
+
+      for (int i = 1; i < inTuple.size(); i++) {
+        translatedTuple.add(inTuple.get(i));
+      }
+
+      // System.out.println("------TRANSLATED " + inTuple + " -> " + translatedTuple);
+      return translatedTuple;
+
+    } else {
+      return inTuple;
+    }
+
+  }
+
+  private MethodSummary getMethodSummary(MethodDescriptor md) {
+    if (!mapDescToLocationSummary.containsKey(md)) {
+      mapDescToLocationSummary.put(md, new MethodSummary(md));
+    }
+    return (MethodSummary) mapDescToLocationSummary.get(md);
+  }
+
+  private void addMapClassDefinitionToLineNum(ClassDescriptor cd, String strLine, int lineNum) {
+
+    String classSymbol = cd.getSymbol();
+    int idx = classSymbol.lastIndexOf("$");
+    if (idx != -1) {
+      classSymbol = classSymbol.substring(idx + 1);
+    }
+
+    String pattern = "class " + classSymbol + " ";
+    if (strLine.indexOf(pattern) != -1) {
+      mapDescToDefinitionLine.put(cd, lineNum);
+    }
+  }
+
+  private void addMapMethodDefinitionToLineNum(Set<MethodDescriptor> methodSet, String strLine,
+      int lineNum) {
+    for (Iterator iterator = methodSet.iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      String pattern = md.getMethodDeclaration();
+      if (strLine.indexOf(pattern) != -1) {
+        mapDescToDefinitionLine.put(md, lineNum);
+        methodSet.remove(md);
+        return;
+      }
+    }
+
+  }
+
+  private void readOriginalSourceFiles() {
+
+    SymbolTable classtable = state.getClassSymbolTable();
+
+    Set<ClassDescriptor> classDescSet = new HashSet<ClassDescriptor>();
+    classDescSet.addAll(classtable.getValueSet());
+
+    try {
+      // inefficient implement. it may re-visit the same file if the file
+      // contains more than one class definitions.
+      for (Iterator iterator = classDescSet.iterator(); iterator.hasNext();) {
+        ClassDescriptor cd = (ClassDescriptor) iterator.next();
+
+        Set<MethodDescriptor> methodSet = new HashSet<MethodDescriptor>();
+        methodSet.addAll(cd.getMethodTable().getValueSet());
+
+        String sourceFileName = cd.getSourceFileName();
+        Vector<String> lineVec = new Vector<String>();
+
+        mapFileNameToLineVector.put(sourceFileName, lineVec);
+
+        BufferedReader in = new BufferedReader(new FileReader(sourceFileName));
+        String strLine;
+        int lineNum = 1;
+        lineVec.add(""); // the index is started from 1.
+        while ((strLine = in.readLine()) != null) {
+          lineVec.add(lineNum, strLine);
+          addMapClassDefinitionToLineNum(cd, strLine, lineNum);
+          addMapMethodDefinitionToLineNum(methodSet, strLine, lineNum);
+          lineNum++;
+        }
+
+      }
+
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
+
+  }
+
+  private String generateLatticeDefinition(Descriptor desc) {
+
+    Set<String> sharedLocSet = new HashSet<String>();
+
+    SSJavaLattice<String> lattice = getLattice(desc);
+    String rtr = "@LATTICE(\"";
+
+    Map<String, Set<String>> map = lattice.getTable();
+    Set<String> keySet = map.keySet();
+
+    // System.out.println("@generateLatticeDefinition=" + desc + "      map=" + map);
+
+    boolean first = true;
+    for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
+      String key = (String) iterator.next();
+      if (!key.equals(lattice.getTopItem())) {
+        Set<String> connectedSet = map.get(key);
+
+        if (connectedSet.size() == 1) {
+          if (connectedSet.iterator().next().equals(lattice.getBottomItem())) {
+            if (!first) {
+              rtr += ",";
+            } else {
+              rtr += "LOC,";
+              first = false;
+            }
+            rtr += key;
+            if (lattice.isSharedLoc(key)) {
+              rtr += "," + key + "*";
+            }
+          }
+        }
+
+        for (Iterator iterator2 = connectedSet.iterator(); iterator2.hasNext();) {
+          String loc = (String) iterator2.next();
+          if (!loc.equals(lattice.getBottomItem())) {
+            if (!first) {
+              rtr += ",";
+            } else {
+              rtr += "LOC,";
+              first = false;
+            }
+            rtr += loc + "<" + key;
+            if (lattice.isSharedLoc(key) && (!sharedLocSet.contains(key))) {
+              rtr += "," + key + "*";
+              sharedLocSet.add(key);
+            }
+            if (lattice.isSharedLoc(loc) && (!sharedLocSet.contains(loc))) {
+              rtr += "," + loc + "*";
+              sharedLocSet.add(loc);
+            }
+
+          }
+        }
+      }
+    }
+
+    if (desc instanceof MethodDescriptor) {
+      // System.out.println("#EXTRA LOC DECLARATION GEN=" + desc);
+
+      MethodDescriptor md = (MethodDescriptor) desc;
+      MethodSummary methodSummary = getMethodSummary(md);
+
+      TypeDescriptor returnType = ((MethodDescriptor) desc).getReturnType();
+      if (!ssjava.getMethodContainingSSJavaLoop().equals(desc) && returnType != null
+          && (!returnType.isVoid())) {
+        CompositeLocation returnLoc = methodSummary.getRETURNLoc();
+        if (returnLoc.getSize() == 1) {
+          String returnLocStr = generateLocationAnnoatation(methodSummary.getRETURNLoc());
+          if (rtr.indexOf(returnLocStr) == -1) {
+            rtr += "," + returnLocStr;
+          }
+        }
+      }
+      rtr += "\")";
+
+      if (!ssjava.getMethodContainingSSJavaLoop().equals(desc)) {
+        if (returnType != null && (!returnType.isVoid())) {
+          rtr +=
+              "\n@RETURNLOC(\"" + generateLocationAnnoatation(methodSummary.getRETURNLoc()) + "\")";
+        }
+
+        CompositeLocation pcLoc = methodSummary.getPCLoc();
+        if ((pcLoc != null) && (!pcLoc.get(0).isTop())) {
+          rtr += "\n@PCLOC(\"" + generateLocationAnnoatation(pcLoc) + "\")";
+        }
+      }
+
+      if (!md.isStatic()) {
+        rtr += "\n@THISLOC(\"" + methodSummary.getThisLocName() + "\")";
+      }
+      rtr += "\n@GLOBALLOC(\"" + methodSummary.getGlobalLocName() + "\")";
+
+    } else {
+      rtr += "\")";
+    }
+
+    return rtr;
+  }
+
+  private void generateAnnoatedCode() {
+
+    readOriginalSourceFiles();
+
+    setupToAnalyze();
+    while (!toAnalyzeIsEmpty()) {
+      ClassDescriptor cd = toAnalyzeNext();
+
+      setupToAnalazeMethod(cd);
+
+      String sourceFileName = cd.getSourceFileName();
+
+      if (cd.isInterface()) {
+        continue;
+      }
+
+      int classDefLine = mapDescToDefinitionLine.get(cd);
+      Vector<String> sourceVec = mapFileNameToLineVector.get(sourceFileName);
+
+      LocationSummary fieldLocSummary = getLocationSummary(cd);
+
+      String fieldLatticeDefStr = generateLatticeDefinition(cd);
+      String annoatedSrc = fieldLatticeDefStr + newline + sourceVec.get(classDefLine);
+      sourceVec.set(classDefLine, annoatedSrc);
+
+      // generate annotations for field declarations
+      // Map<Descriptor, CompositeLocation> inferLocMap = fieldLocInfo.getMapDescToInferLocation();
+      Map<String, String> mapFieldNameToLocName = fieldLocSummary.getMapHNodeNameToLocationName();
+
+      for (Iterator iter = cd.getFields(); iter.hasNext();) {
+        FieldDescriptor fd = (FieldDescriptor) iter.next();
+
+        String locAnnotationStr;
+        // CompositeLocation inferLoc = inferLocMap.get(fd);
+        String locName = mapFieldNameToLocName.get(fd.getSymbol());
+
+        if (locName != null) {
+          // infer loc is null if the corresponding field is static and final
+          // locAnnotationStr = "@LOC(\"" + generateLocationAnnoatation(inferLoc) + "\")";
+          locAnnotationStr = "@LOC(\"" + locName + "\")";
+          int fdLineNum = fd.getLineNum();
+          String orgFieldDeclarationStr = sourceVec.get(fdLineNum);
+          String fieldDeclaration = fd.toString();
+          fieldDeclaration = fieldDeclaration.substring(0, fieldDeclaration.length() - 1);
+          String annoatedStr = locAnnotationStr + " " + orgFieldDeclarationStr;
+          sourceVec.set(fdLineNum, annoatedStr);
+        }
+
+      }
+
+      while (!toAnalyzeMethodIsEmpty()) {
+        MethodDescriptor md = toAnalyzeMethodNext();
+
+        if (!ssjava.needTobeAnnotated(md)) {
+          continue;
+        }
+
+        SSJavaLattice<String> methodLattice = md2lattice.get(md);
+        // System.out.println("md=" + md + " methodLattice=" + methodLattice);
+        if (methodLattice != null) {
+
+          int methodDefLine = md.getLineNum();
+
+          // MethodLocationInfo methodLocInfo = getMethodLocationInfo(md);
+          // Map<Descriptor, CompositeLocation> methodInferLocMap =
+          // methodLocInfo.getMapDescToInferLocation();
+
+          MethodSummary methodSummary = getMethodSummary(md);
+
+          Map<Descriptor, CompositeLocation> mapVarDescToInferLoc =
+              methodSummary.getMapVarDescToInferCompositeLocation();
+          // System.out.println("-----md=" + md + " methodDefLine=" + methodDefLine);
+          // System.out.println("-----mapVarDescToInferLoc=" + mapVarDescToInferLoc);
+
+          Set<Descriptor> localVarDescSet = mapVarDescToInferLoc.keySet();
+
+          Set<String> localLocElementSet = methodLattice.getElementSet();
+
+          for (Iterator iterator = localVarDescSet.iterator(); iterator.hasNext();) {
+            Descriptor localVarDesc = (Descriptor) iterator.next();
+            // System.out.println("-------localVarDesc=" + localVarDesc);
+            CompositeLocation inferLoc = mapVarDescToInferLoc.get(localVarDesc);
+
+            String localLocIdentifier = inferLoc.get(0).getLocIdentifier();
+            if (!localLocElementSet.contains(localLocIdentifier)) {
+              methodLattice.put(localLocIdentifier);
+            }
+
+            String locAnnotationStr = "@LOC(\"" + generateLocationAnnoatation(inferLoc) + "\")";
+
+            if (!isParameter(md, localVarDesc)) {
+              if (mapDescToDefinitionLine.containsKey(localVarDesc)) {
+                int varLineNum = mapDescToDefinitionLine.get(localVarDesc);
+                String orgSourceLine = sourceVec.get(varLineNum);
+                // System.out.println("varLineNum=" + varLineNum + "  org src=" + orgSourceLine);
+                int idx =
+                    orgSourceLine.indexOf(generateVarDeclaration((VarDescriptor) localVarDesc));
+                // System.out.println("idx=" + idx
+                // + "  generateVarDeclaration((VarDescriptor) localVarDesc)="
+                // + generateVarDeclaration((VarDescriptor) localVarDesc));
+                assert (idx != -1);
+                String annoatedStr =
+                    orgSourceLine.substring(0, idx) + locAnnotationStr + " "
+                        + orgSourceLine.substring(idx);
+                sourceVec.set(varLineNum, annoatedStr);
+              }
+            } else {
+              String methodDefStr = sourceVec.get(methodDefLine);
+
+              int idx =
+                  getParamLocation(methodDefStr,
+                      generateVarDeclaration((VarDescriptor) localVarDesc));
+              // System.out.println("methodDefStr=" + methodDefStr + " localVarDesc=" + localVarDesc
+              // + " idx=" + idx);
+              assert (idx != -1);
+
+              String annoatedStr =
+                  methodDefStr.substring(0, idx) + locAnnotationStr + " "
+                      + methodDefStr.substring(idx);
+              sourceVec.set(methodDefLine, annoatedStr);
+            }
+
+          }
+
+          // check if the lattice has to have the location type for the this
+          // reference...
+
+          // boolean needToAddthisRef = hasThisReference(md);
+          // if (localLocElementSet.contains("this")) {
+          // methodLattice.put("this");
+          // }
+
+          String methodLatticeDefStr = generateLatticeDefinition(md);
+          String annoatedStr = methodLatticeDefStr + newline + sourceVec.get(methodDefLine);
+          sourceVec.set(methodDefLine, annoatedStr);
+
+        }
+      }
+
+    }
+
+    codeGen();
+  }
+
+  private boolean hasThisReference(MethodDescriptor md) {
+
+    FlowGraph fg = getFlowGraph(md);
+    Set<FlowNode> nodeSet = fg.getNodeSet();
+    for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+      FlowNode flowNode = (FlowNode) iterator.next();
+      if (flowNode.getDescTuple().get(0).equals(md.getThis())) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  private int getParamLocation(String methodStr, String paramStr) {
+
+    String pattern = paramStr + ",";
+
+    int idx = methodStr.indexOf(pattern);
+    if (idx != -1) {
+      return idx;
+    } else {
+      pattern = paramStr + ")";
+      return methodStr.indexOf(pattern);
+    }
+
+  }
+
+  private String generateVarDeclaration(VarDescriptor varDesc) {
+
+    TypeDescriptor td = varDesc.getType();
+    String rtr = td.toString();
+    if (td.isArray()) {
+      for (int i = 0; i < td.getArrayCount(); i++) {
+        rtr += "[]";
+      }
+    }
+    rtr += " " + varDesc.getName();
+    return rtr;
+
+  }
+
+  private String generateLocationAnnoatation(CompositeLocation loc) {
+    String rtr = "";
+    // method location
+    Location methodLoc = loc.get(0);
+    rtr += methodLoc.getLocIdentifier();
+
+    for (int i = 1; i < loc.getSize(); i++) {
+      Location element = loc.get(i);
+      rtr += "," + element.getDescriptor().getSymbol() + "." + element.getLocIdentifier();
+    }
+
+    return rtr;
+  }
+
+  private boolean isParameter(MethodDescriptor md, Descriptor localVarDesc) {
+    return getFlowGraph(md).isParamDesc(localVarDesc);
+  }
+
+  private String extractFileName(String fileName) {
+    int idx = fileName.lastIndexOf("/");
+    if (idx == -1) {
+      return fileName;
+    } else {
+      return fileName.substring(idx + 1);
+    }
+
+  }
+
+  private void codeGen() {
+
+    Set<String> originalFileNameSet = mapFileNameToLineVector.keySet();
+    for (Iterator iterator = originalFileNameSet.iterator(); iterator.hasNext();) {
+      String orgFileName = (String) iterator.next();
+      String outputFileName = extractFileName(orgFileName);
+
+      Vector<String> sourceVec = mapFileNameToLineVector.get(orgFileName);
+
+      try {
+
+        FileWriter fileWriter = new FileWriter("./infer/" + outputFileName);
+        BufferedWriter out = new BufferedWriter(fileWriter);
+
+        for (int i = 0; i < sourceVec.size(); i++) {
+          out.write(sourceVec.get(i));
+          out.newLine();
+        }
+        out.close();
+      } catch (IOException e) {
+        e.printStackTrace();
+      }
+
+    }
+
+  }
+
+  private void checkLattices() {
+
+    LinkedList<MethodDescriptor> descriptorListToAnalyze = ssjava.getSortedDescriptors();
+
+    // current descriptors to visit in fixed-point interprocedural analysis,
+    // prioritized by
+    // dependency in the call graph
+    methodDescriptorsToVisitStack.clear();
+
+    // descriptorListToAnalyze.removeFirst();
+
+    Set<MethodDescriptor> methodDescriptorToVistSet = new HashSet<MethodDescriptor>();
+    methodDescriptorToVistSet.addAll(descriptorListToAnalyze);
+
+    while (!descriptorListToAnalyze.isEmpty()) {
+      MethodDescriptor md = descriptorListToAnalyze.removeFirst();
+      checkLatticesOfVirtualMethods(md);
+    }
+
+  }
+
+  private void debug_writeLatticeDotFile() {
+    // generate lattice dot file
+
+    setupToAnalyze();
+
+    while (!toAnalyzeIsEmpty()) {
+      ClassDescriptor cd = toAnalyzeNext();
+
+      setupToAnalazeMethod(cd);
+
+      SSJavaLattice<String> classLattice = cd2lattice.get(cd);
+      if (classLattice != null) {
+        ssjava.writeLatticeDotFile(cd, null, classLattice);
+        // debug_printDescriptorToLocNameMapping(cd);
+      }
+
+      while (!toAnalyzeMethodIsEmpty()) {
+        MethodDescriptor md = toAnalyzeMethodNext();
+        SSJavaLattice<String> methodLattice = md2lattice.get(md);
+        if (methodLattice != null) {
+          ssjava.writeLatticeDotFile(cd, md, methodLattice);
+          // debug_printDescriptorToLocNameMapping(md);
+        }
+      }
+    }
+
+  }
+
+  private void debug_printDescriptorToLocNameMapping(Descriptor desc) {
+
+    LocationInfo info = getLocationInfo(desc);
+    System.out.println("## " + desc + " ##");
+    System.out.println(info.getMapDescToInferLocation());
+    LocationInfo locInfo = getLocationInfo(desc);
+    System.out.println("mapping=" + locInfo.getMapLocSymbolToDescSet());
+    System.out.println("###################");
+
+  }
+
+  private void calculateExtraLocations() {
+
+    // LinkedList<MethodDescriptor> methodDescList = ssjava.getSortedDescriptors();
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+    for (Iterator iterator = methodDescList.iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      if (!ssjava.getMethodContainingSSJavaLoop().equals(md)) {
+        calculateExtraLocations(md);
+      }
+    }
+
+  }
+
+  private void checkLatticesOfVirtualMethods(MethodDescriptor md) {
+
+    if (!md.isStatic()) {
+      Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
+      setPossibleCallees.addAll(ssjava.getCallGraph().getMethods(md));
+
+      for (Iterator iterator = setPossibleCallees.iterator(); iterator.hasNext();) {
+        MethodDescriptor mdCallee = (MethodDescriptor) iterator.next();
+        if (!md.equals(mdCallee)) {
+          checkConsistency(md, mdCallee);
+        }
+      }
+
+    }
+
+  }
+
+  private void checkConsistency(MethodDescriptor md1, MethodDescriptor md2) {
+
+    // check that two lattice have the same relations between parameters(+PC
+    // LOC, GLOBAL_LOC RETURN LOC)
+
+    List<CompositeLocation> list1 = new ArrayList<CompositeLocation>();
+    List<CompositeLocation> list2 = new ArrayList<CompositeLocation>();
+
+    MethodLocationInfo locInfo1 = getMethodLocationInfo(md1);
+    MethodLocationInfo locInfo2 = getMethodLocationInfo(md2);
+
+    Map<Integer, CompositeLocation> paramMap1 = locInfo1.getMapParamIdxToInferLoc();
+    Map<Integer, CompositeLocation> paramMap2 = locInfo2.getMapParamIdxToInferLoc();
+
+    int numParam = locInfo1.getMapParamIdxToInferLoc().keySet().size();
+
+    // add location types of paramters
+    for (int idx = 0; idx < numParam; idx++) {
+      list1.add(paramMap1.get(Integer.valueOf(idx)));
+      list2.add(paramMap2.get(Integer.valueOf(idx)));
+    }
+
+    // add program counter location
+    list1.add(locInfo1.getPCLoc());
+    list2.add(locInfo2.getPCLoc());
+
+    if (!md1.getReturnType().isVoid()) {
+      // add return value location
+      CompositeLocation rtrLoc1 = getMethodLocationInfo(md1).getReturnLoc();
+      CompositeLocation rtrLoc2 = getMethodLocationInfo(md2).getReturnLoc();
+      list1.add(rtrLoc1);
+      list2.add(rtrLoc2);
+    }
+
+    // add global location type
+    if (md1.isStatic()) {
+      CompositeLocation globalLoc1 =
+          new CompositeLocation(new Location(md1, locInfo1.getGlobalLocName()));
+      CompositeLocation globalLoc2 =
+          new CompositeLocation(new Location(md2, locInfo2.getGlobalLocName()));
+      list1.add(globalLoc1);
+      list2.add(globalLoc2);
+    }
+
+    for (int i = 0; i < list1.size(); i++) {
+      CompositeLocation locA1 = list1.get(i);
+      CompositeLocation locA2 = list2.get(i);
+      for (int k = 0; k < list1.size(); k++) {
+        if (i != k) {
+          CompositeLocation locB1 = list1.get(k);
+          CompositeLocation locB2 = list2.get(k);
+          boolean r1 = isGreaterThan(getLattice(md1), locA1, locB1);
+
+          boolean r2 = isGreaterThan(getLattice(md1), locA2, locB2);
+
+          if (r1 != r2) {
+            throw new Error("The method " + md1 + " is not consistent with the method " + md2
+                + ".:: They have a different ordering relation between locations (" + locA1 + ","
+                + locB1 + ") and (" + locA2 + "," + locB2 + ").");
+          }
+        }
+      }
+    }
+
+  }
+
+  private String getSymbol(int idx, FlowNode node) {
+    Descriptor desc = node.getDescTuple().get(idx);
+    return desc.getSymbol();
+  }
+
+  private Descriptor getDescriptor(int idx, FlowNode node) {
+    Descriptor desc = node.getDescTuple().get(idx);
+    return desc;
+  }
+
+  private void calculatePCLOC(MethodDescriptor md) {
+
+    // System.out.println("#CalculatePCLOC");
+    MethodSummary methodSummary = getMethodSummary(md);
+    FlowGraph fg = getFlowGraph(md);
+    Map<Integer, CompositeLocation> mapParamToLoc = methodSummary.getMapParamIdxToInferLoc();
+
+    // calculate the initial program counter location
+    // PC location is higher than location types of parameters which has incoming flows.
+
+    Set<NTuple<Location>> paramLocTupleHavingInFlowSet = new HashSet<NTuple<Location>>();
+    Set<Descriptor> paramDescNOTHavingInFlowSet = new HashSet<Descriptor>();
+    // Set<FlowNode> paramNodeNOThavingInFlowSet = new HashSet<FlowNode>();
+
+    int numParams = fg.getNumParameters();
+    for (int i = 0; i < numParams; i++) {
+      FlowNode paramFlowNode = fg.getParamFlowNode(i);
+      Descriptor prefix = paramFlowNode.getDescTuple().get(0);
+      NTuple<Descriptor> paramDescTuple = paramFlowNode.getCurrentDescTuple();
+      NTuple<Location> paramLocTuple = translateToLocTuple(md, paramDescTuple);
+
+      Set<FlowNode> inNodeToParamSet = fg.getIncomingNodeSetByPrefix(prefix);
+      if (inNodeToParamSet.size() > 0) {
+        // parameter has in-value flows
+
+        for (Iterator iterator = inNodeToParamSet.iterator(); iterator.hasNext();) {
+          FlowNode inNode = (FlowNode) iterator.next();
+          Set<FlowEdge> outEdgeSet = fg.getOutEdgeSet(inNode);
+          for (Iterator iterator2 = outEdgeSet.iterator(); iterator2.hasNext();) {
+            FlowEdge flowEdge = (FlowEdge) iterator2.next();
+            if (flowEdge.getEndTuple().startsWith(prefix)) {
+              NTuple<Location> paramLocTupleWithIncomingFlow =
+                  translateToLocTuple(md, flowEdge.getEndTuple());
+              paramLocTupleHavingInFlowSet.add(paramLocTupleWithIncomingFlow);
+            }
+          }
+        }
+
+        // paramLocTupleHavingInFlowSet.add(paramLocTuple);
+      } else {
+        // paramNodeNOThavingInFlowSet.add(fg.getFlowNode(paramDescTuple));
+        paramDescNOTHavingInFlowSet.add(prefix);
+      }
+    }
+
+    // System.out.println("paramLocTupleHavingInFlowSet=" + paramLocTupleHavingInFlowSet);
+
+    if (paramLocTupleHavingInFlowSet.size() > 0
+        && !coversAllParamters(md, fg, paramLocTupleHavingInFlowSet)) {
+
+      // Here, generates a location in the method lattice that is higher than the
+      // paramLocTupleHavingInFlowSet
+      NTuple<Location> pcLocTuple =
+          generateLocTupleRelativeTo(md, paramLocTupleHavingInFlowSet, PCLOC);
+
+      NTuple<Descriptor> pcDescTuple = translateToDescTuple(pcLocTuple);
+
+      // System.out.println("pcLoc=" + pcLocTuple);
+
+      CompositeLocation curPCLoc = methodSummary.getPCLoc();
+      if (curPCLoc.get(0).isTop() || pcLocTuple.size() > curPCLoc.getSize()) {
+        methodSummary.setPCLoc(new CompositeLocation(pcLocTuple));
+
+        Set<FlowNode> flowNodeLowerthanPCLocSet = new HashSet<FlowNode>();
+        GlobalFlowGraph subGlobalFlowGraph = getSubGlobalFlowGraph(md);
+        // add ordering relations s.t. PCLOC is higher than all flow nodes except the set of
+        // parameters that do not have incoming flows
+        for (Iterator iterator = fg.getNodeSet().iterator(); iterator.hasNext();) {
+          FlowNode node = (FlowNode) iterator.next();
+
+          if (!(node instanceof FlowReturnNode)) {
+            if (!paramDescNOTHavingInFlowSet.contains(node.getCurrentDescTuple().get(0))) {
+              flowNodeLowerthanPCLocSet.add(node);
+              fg.addValueFlowEdge(pcDescTuple, node.getDescTuple());
+
+              subGlobalFlowGraph.addValueFlowEdge(pcLocTuple,
+                  translateToLocTuple(md, node.getDescTuple()));
+            }
+          } else {
+            // System.out.println("***SKIP PCLOC -> RETURNLOC=" + node);
+          }
+
+        }
+        fg.getFlowNode(translateToDescTuple(pcLocTuple)).setSkeleton(true);
+
+        if (pcLocTuple.get(0).getLocDescriptor().equals(md.getThis())) {
+          for (Iterator iterator = flowNodeLowerthanPCLocSet.iterator(); iterator.hasNext();) {
+            FlowNode lowerNode = (FlowNode) iterator.next();
+            if (lowerNode.getDescTuple().size() == 1 && lowerNode.getCompositeLocation() == null) {
+              NTuple<Location> lowerLocTuple = translateToLocTuple(md, lowerNode.getDescTuple());
+              CompositeLocation newComp =
+                  calculateCompositeLocationFromSubGlobalGraph(md, lowerNode);
+              if (newComp != null) {
+                subGlobalFlowGraph.addMapLocationToInferCompositeLocation(lowerLocTuple.get(0),
+                    newComp);
+                lowerNode.setCompositeLocation(newComp);
+                // System.out.println("NEW COMP LOC=" + newComp + "    to lowerNode=" + lowerNode);
+              }
+
+            }
+
+          }
+        }
+
+      }
+
+    }
+  }
+
+  private int countFirstDescriptorSetSize(Set<NTuple<Location>> set) {
+
+    Set<Descriptor> descSet = new HashSet<Descriptor>();
+
+    for (Iterator iterator = set.iterator(); iterator.hasNext();) {
+      NTuple<Location> locTuple = (NTuple<Location>) iterator.next();
+      descSet.add(locTuple.get(0).getLocDescriptor());
+    }
+
+    return descSet.size();
+  }
+
+  private boolean coversAllParamters(MethodDescriptor md, FlowGraph fg,
+      Set<NTuple<Location>> paramLocTupleHavingInFlowSet) {
+
+    int numParam = fg.getNumParameters();
+    // int size = paramLocTupleHavingInFlowSet.size();
+    int size = countFirstDescriptorSetSize(paramLocTupleHavingInFlowSet);
+
+    // System.out.println("numParam=" + numParam + "     size=" + size);
+
+    // if (!md.isStatic()) {
+    //
+    // // if the method is not static && there is a parameter composite location &&
+    // // it is started with 'this',
+    // // paramLocTupleHavingInFlowSet need to have 'this' parameter.
+    //
+    // FlowNode thisParamNode = fg.getParamFlowNode(0);
+    // NTuple<Location> thisParamLocTuple =
+    // translateToLocTuple(md, thisParamNode.getCurrentDescTuple());
+    //
+    // if (!paramLocTupleHavingInFlowSet.contains(thisParamLocTuple)) {
+    //
+    // for (Iterator iterator = paramLocTupleHavingInFlowSet.iterator(); iterator.hasNext();) {
+    // NTuple<Location> paramTuple = (NTuple<Location>) iterator.next();
+    // if (paramTuple.size() > 1 && paramTuple.get(0).getLocDescriptor().equals(md.getThis())) {
+    // // paramLocTupleHavingInFlowSet.add(thisParamLocTuple);
+    // // break;
+    // size++;
+    // }
+    // }
+    //
+    // }
+    // }
+
+    if (size == numParam) {
+      return true;
+    } else {
+      return false;
+    }
+
+  }
+
+  private void calculateRETURNLOC(MethodDescriptor md) {
+
+    // System.out.println("#calculateRETURNLOC= " + md);
+
+    // calculate a return location:
+    // the return location type is lower than all parameters and the location of return values
+    MethodSummary methodSummary = getMethodSummary(md);
+    // if (methodSummary.getRETURNLoc() != null) {
+    // System.out.println("$HERE?");
+    // return;
+    // }
+
+    FlowGraph fg = getFlowGraph(md);
+    Map<Integer, CompositeLocation> mapParamToLoc = methodSummary.getMapParamIdxToInferLoc();
+    Set<Integer> paramIdxSet = mapParamToLoc.keySet();
+
+    if (md.getReturnType() != null && !md.getReturnType().isVoid()) {
+      // first, generate the set of return value location types that starts
+      // with 'this' reference
+
+      Set<FlowNode> paramFlowNodeFlowingToReturnValueSet = getParamNodeFlowingToReturnValue(md);
+      // System.out.println("paramFlowNodeFlowingToReturnValueSet="
+      // + paramFlowNodeFlowingToReturnValueSet);
+
+      Set<NTuple<Location>> tupleToBeHigherThanReturnLocSet = new HashSet<NTuple<Location>>();
+      for (Iterator iterator = paramFlowNodeFlowingToReturnValueSet.iterator(); iterator.hasNext();) {
+        FlowNode fn = (FlowNode) iterator.next();
+        NTuple<Descriptor> paramDescTuple = fn.getCurrentDescTuple();
+        tupleToBeHigherThanReturnLocSet.add(translateToLocTuple(md, paramDescTuple));
+      }
+
+      Set<FlowNode> returnNodeSet = fg.getReturnNodeSet();
+      for (Iterator iterator = returnNodeSet.iterator(); iterator.hasNext();) {
+        FlowNode returnNode = (FlowNode) iterator.next();
+        NTuple<Descriptor> returnDescTuple = returnNode.getCurrentDescTuple();
+        tupleToBeHigherThanReturnLocSet.add(translateToLocTuple(md, returnDescTuple));
+      }
+      // System.out.println("-flow graph's returnNodeSet=" + returnNodeSet);
+      // System.out.println("tupleSetToBeHigherThanReturnLoc=" + tupleToBeHigherThanReturnLocSet);
+
+      // Here, generates a return location in the method lattice that is lower than the
+      // locFlowingToReturnValueSet
+      NTuple<Location> returnLocTuple =
+          generateLocTupleRelativeTo(md, tupleToBeHigherThanReturnLocSet, RLOC);
+
+      // System.out.println("returnLocTuple=" + returnLocTuple);
+      NTuple<Descriptor> returnDescTuple = translateToDescTuple(returnLocTuple);
+      CompositeLocation curReturnLoc = methodSummary.getRETURNLoc();
+      if (curReturnLoc == null || returnDescTuple.size() > curReturnLoc.getSize()) {
+        methodSummary.setRETURNLoc(new CompositeLocation(returnLocTuple));
+
+        for (Iterator iterator = tupleToBeHigherThanReturnLocSet.iterator(); iterator.hasNext();) {
+          NTuple<Location> higherTuple = (NTuple<Location>) iterator.next();
+          fg.addValueFlowEdge(translateToDescTuple(higherTuple), returnDescTuple);
+        }
+        fg.getFlowNode(returnDescTuple).setSkeleton(true);
+
+      }
+
+      // makes sure that PCLOC is higher than RETURNLOC
+      CompositeLocation pcLoc = methodSummary.getPCLoc();
+      if (!pcLoc.get(0).isTop()) {
+        NTuple<Descriptor> pcLocDescTuple = translateToDescTuple(pcLoc.getTuple());
+        fg.addValueFlowEdge(pcLocDescTuple, returnDescTuple);
+      }
+
+    }
+
+  }
+
+  private void calculateExtraLocations(MethodDescriptor md) {
+    // calcualte pcloc, returnloc,...
+
+    System.out.println("\nSSJAVA:Calculate PCLOC/RETURNLOC locations: " + md);
+
+    calculatePCLOC(md);
+    calculateRETURNLOC(md);
+
+  }
+
+  private NTuple<Location> generateLocTupleRelativeTo(MethodDescriptor md,
+      Set<NTuple<Location>> paramLocTupleHavingInFlowSet, String locNamePrefix) {
+
+    // System.out.println("-generateLocTupleRelativeTo=" + paramLocTupleHavingInFlowSet);
+
+    NTuple<Location> higherLocTuple = new NTuple<Location>();
+
+    VarDescriptor thisVarDesc = md.getThis();
+    // check if all paramter loc tuple is started with 'this' reference
+    boolean hasParamNotStartedWithThisRef = false;
+
+    int minSize = 0;
+
+    Set<NTuple<Location>> paramLocTupleStartedWithThis = new HashSet<NTuple<Location>>();
+
+    next: for (Iterator iterator = paramLocTupleHavingInFlowSet.iterator(); iterator.hasNext();) {
+      NTuple<Location> paramLocTuple = (NTuple<Location>) iterator.next();
+      Descriptor paramLocalDesc = paramLocTuple.get(0).getLocDescriptor();
+      if (!paramLocalDesc.equals(thisVarDesc)) {
+
+        Set<FlowNode> inNodeSet = getFlowGraph(md).getIncomingNodeSetByPrefix(paramLocalDesc);
+        for (Iterator iterator2 = inNodeSet.iterator(); iterator2.hasNext();) {
+          FlowNode flowNode = (FlowNode) iterator2.next();
+          if (flowNode.getDescTuple().startsWith(thisVarDesc)) {
+            // System.out.println("paramLocTuple=" + paramLocTuple + " is lower than THIS");
+            continue next;
+          }
+        }
+        hasParamNotStartedWithThisRef = true;
+
+      } else if (paramLocTuple.size() > 1) {
+        paramLocTupleStartedWithThis.add(paramLocTuple);
+        if (minSize == 0 || minSize > paramLocTuple.size()) {
+          minSize = paramLocTuple.size();
+        }
+      }
+    }
+
+    // System.out.println("---paramLocTupleStartedWithThis=" + paramLocTupleStartedWithThis);
+    Descriptor enclosingDesc = md;
+    if (hasParamNotStartedWithThisRef) {
+      // in this case, PCLOC will be the local location
+    } else {
+      // all parameter is started with 'this', so PCLOC will be set relative to the composite
+      // location started with 'this'.
+      // for (int idx = 0; idx < minSize - 1; idx++) {
+      for (int idx = 0; idx < 1; idx++) {
+        Set<Descriptor> locDescSet = new HashSet<Descriptor>();
+        Location curLoc = null;
+        NTuple<Location> paramLocTuple = null;
+        for (Iterator iterator = paramLocTupleStartedWithThis.iterator(); iterator.hasNext();) {
+          paramLocTuple = (NTuple<Location>) iterator.next();
+          // System.out.println("-----paramLocTuple=" + paramLocTuple + "  idx=" + idx);
+          curLoc = paramLocTuple.get(idx);
+          Descriptor locDesc = curLoc.getLocDescriptor();
+          locDescSet.add(locDesc);
+        }
+        // System.out.println("-----locDescSet=" + locDescSet + " idx=" + idx);
+        if (locDescSet.size() != 1) {
+          break;
+        }
+        Location newLocElement = new Location(curLoc.getDescriptor(), curLoc.getLocDescriptor());
+        // System.out.println("newLocElement" + newLocElement);
+        higherLocTuple.add(newLocElement);
+        enclosingDesc = getClassTypeDescriptor(curLoc.getLocDescriptor());
+      }
+
+    }
+
+    String locIdentifier = locNamePrefix + (locSeed++);
+    NameDescriptor locDesc = new NameDescriptor(locIdentifier);
+    Location newLoc = new Location(enclosingDesc, locDesc);
+    higherLocTuple.add(newLoc);
+    // System.out.println("---new loc tuple=" + higherLocTuple);
+
+    return higherLocTuple;
+
+  }
+
+  public ClassDescriptor getClassTypeDescriptor(Descriptor in) {
+
+    if (in instanceof VarDescriptor) {
+      return ((VarDescriptor) in).getType().getClassDesc();
+    } else if (in instanceof FieldDescriptor) {
+      return ((FieldDescriptor) in).getType().getClassDesc();
+    }
+    // else if (in instanceof LocationDescriptor) {
+    // // here is the case that the descriptor 'in' is the last element of the assigned composite
+    // // location
+    // return ((VarDescriptor) locTuple.get(0).getLocDescriptor()).getType().getClassDesc();
+    // }
+    else {
+      return null;
+    }
+
+  }
+
+  private Set<NTuple<Location>> calculateHighestLocTupleSet(
+      Set<NTuple<Location>> paramLocTupleHavingInFlowSet) {
+
+    Set<NTuple<Location>> highestSet = new HashSet<NTuple<Location>>();
+
+    Iterator<NTuple<Location>> iterator = paramLocTupleHavingInFlowSet.iterator();
+    NTuple<Location> highest = iterator.next();
+
+    for (; iterator.hasNext();) {
+      NTuple<Location> curLocTuple = (NTuple<Location>) iterator.next();
+      if (isHigherThan(curLocTuple, highest)) {
+        // System.out.println(curLocTuple + " is greater than " + highest);
+        highest = curLocTuple;
+      }
+    }
+
+    highestSet.add(highest);
+
+    MethodDescriptor md = (MethodDescriptor) highest.get(0).getDescriptor();
+    VarDescriptor thisVarDesc = md.getThis();
+
+    // System.out.println("highest=" + highest);
+
+    for (Iterator<NTuple<Location>> iter = paramLocTupleHavingInFlowSet.iterator(); iter.hasNext();) {
+      NTuple<Location> curLocTuple = iter.next();
+
+      if (!curLocTuple.equals(highest) && !hasOrderingRelation(highest, curLocTuple)) {
+
+        // System.out.println("add it to the highest set=" + curLocTuple);
+        highestSet.add(curLocTuple);
+
+      }
+    }
+
+    return highestSet;
+
+  }
+
+  private Set<String> getHigherLocSymbolThan(SSJavaLattice<String> lattice, String loc) {
+    Set<String> higherLocSet = new HashSet<String>();
+
+    Set<String> locSet = lattice.getTable().keySet();
+    for (Iterator iterator = locSet.iterator(); iterator.hasNext();) {
+      String element = (String) iterator.next();
+      if (lattice.isGreaterThan(element, loc) && (!element.equals(lattice.getTopItem()))) {
+        higherLocSet.add(element);
+      }
+    }
+    return higherLocSet;
+  }
+
+  private CompositeLocation getLowest(SSJavaLattice<String> methodLattice,
+      Set<CompositeLocation> set) {
+
+    CompositeLocation lowest = set.iterator().next();
+
+    if (set.size() == 1) {
+      return lowest;
+    }
+
+    for (Iterator iterator = set.iterator(); iterator.hasNext();) {
+      CompositeLocation loc = (CompositeLocation) iterator.next();
+
+      if ((!loc.equals(lowest)) && (!isComparable(methodLattice, lowest, loc))) {
+        // if there is a case where composite locations are incomparable, just
+        // return null
+        return null;
+      }
+
+      if ((!loc.equals(lowest)) && isGreaterThan(methodLattice, lowest, loc)) {
+        lowest = loc;
+      }
+    }
+    return lowest;
+  }
+
+  private boolean isComparable(SSJavaLattice<String> methodLattice, CompositeLocation comp1,
+      CompositeLocation comp2) {
+
+    int size = comp1.getSize() >= comp2.getSize() ? comp2.getSize() : comp1.getSize();
+
+    for (int idx = 0; idx < size; idx++) {
+      Location loc1 = comp1.get(idx);
+      Location loc2 = comp2.get(idx);
+
+      Descriptor desc1 = loc1.getDescriptor();
+      Descriptor desc2 = loc2.getDescriptor();
+
+      if (!desc1.equals(desc2)) {
+        throw new Error("Fail to compare " + comp1 + " and " + comp2);
+      }
+
+      String symbol1 = loc1.getLocIdentifier();
+      String symbol2 = loc2.getLocIdentifier();
+
+      SSJavaLattice<String> lattice;
+      if (idx == 0) {
+        lattice = methodLattice;
+      } else {
+        lattice = getLattice(desc1);
+      }
+
+      if (symbol1.equals(symbol2)) {
+        continue;
+      } else if (!lattice.isComparable(symbol1, symbol2)) {
+        return false;
+      }
+
+    }
+
+    return true;
+  }
+
+  private boolean isGreaterThan(SSJavaLattice<String> methodLattice, CompositeLocation comp1,
+      CompositeLocation comp2) {
+
+    int size = comp1.getSize() >= comp2.getSize() ? comp2.getSize() : comp1.getSize();
+
+    for (int idx = 0; idx < size; idx++) {
+      Location loc1 = comp1.get(idx);
+      Location loc2 = comp2.get(idx);
+
+      Descriptor desc1 = loc1.getDescriptor();
+      Descriptor desc2 = loc2.getDescriptor();
+
+      if (!desc1.equals(desc2)) {
+        throw new Error("Fail to compare " + comp1 + " and " + comp2);
+      }
+
+      String symbol1 = loc1.getLocIdentifier();
+      String symbol2 = loc2.getLocIdentifier();
+
+      SSJavaLattice<String> lattice;
+      if (idx == 0) {
+        lattice = methodLattice;
+      } else {
+        lattice = getLattice(desc1);
+      }
+
+      if (symbol1.equals(symbol2)) {
+        continue;
+      } else if (lattice.isGreaterThan(symbol1, symbol2)) {
+        return true;
+      } else {
+        return false;
+      }
+
+    }
+
+    return false;
+  }
+
+  private GlobalFlowGraph getSubGlobalFlowGraph(MethodDescriptor md) {
+
+    if (!mapMethodDescriptorToSubGlobalFlowGraph.containsKey(md)) {
+      mapMethodDescriptorToSubGlobalFlowGraph.put(md, new GlobalFlowGraph(md));
+    }
+    return mapMethodDescriptorToSubGlobalFlowGraph.get(md);
+  }
+
+  private void propagateFlowsToCallerWithNoCompositeLocation(MethodInvokeNode min,
+      MethodDescriptor mdCaller, MethodDescriptor mdCallee) {
+
+    // System.out.println("-propagateFlowsToCallerWithNoCompositeLocation=" + min.printNode(0));
+    // if the parameter A reaches to the parameter B
+    // then, add an edge the argument A -> the argument B to the caller's flow
+    // graph
+
+    FlowGraph calleeFlowGraph = getFlowGraph(mdCallee);
+    FlowGraph callerFlowGraph = getFlowGraph(mdCaller);
+    int numParam = calleeFlowGraph.getNumParameters();
+
+    for (int i = 0; i < numParam; i++) {
+      for (int k = 0; k < numParam; k++) {
+
+        if (i != k) {
+
+          FlowNode paramNode1 = calleeFlowGraph.getParamFlowNode(i);
+          FlowNode paramNode2 = calleeFlowGraph.getParamFlowNode(k);
+
+          NTuple<Descriptor> arg1Tuple = getNodeTupleByArgIdx(min, i);
+          NTuple<Descriptor> arg2Tuple = getNodeTupleByArgIdx(min, k);
+
+          // check if the callee propagates an ordering constraints through
+          // parameters
+
+          // Set<FlowNode> localReachSet = calleeFlowGraph.getLocalReachFlowNodeSetFrom(paramNode1);
+          Set<FlowNode> localReachSet =
+              calleeFlowGraph.getReachableSetFrom(paramNode1.getDescTuple());
+
+          NTuple<Descriptor> paramDescTuple1 = paramNode1.getCurrentDescTuple();
+          NTuple<Descriptor> paramDescTuple2 = paramNode2.getCurrentDescTuple();
+
+          // System.out.println("-param1CurTuple=" + paramDescTuple1 + " param2CurTuple="
+          // + paramDescTuple2);
+          // System.out.println("-- localReachSet from param1=" + localReachSet);
+
+          if (paramDescTuple1.get(0).equals(paramDescTuple2.get(0))) {
+            // if two parameters share the same prefix
+            // it already has been assigned to a composite location
+            // so we don't need to add an additional ordering relation caused by these two
+            // paramters.
+            continue;
+          }
+
+          if (arg1Tuple.size() > 0 && arg2Tuple.size() > 0
+              && containsPrefix(paramNode2.getDescTuple().get(0), localReachSet)) {
+            // need to propagate an ordering relation s.t. arg1 is higher
+            // than arg2
+            // System.out.println("-param1=" + paramNode1 + " is higher than param2=" + paramNode2);
+
+            // add a new flow between the corresponding arguments.
+            callerFlowGraph.addValueFlowEdge(arg1Tuple, arg2Tuple);
+            // System.out.println("arg1=" + arg1Tuple + "   arg2=" + arg2Tuple);
+
+            // System.out
+            // .println("-arg1Tuple=" + arg1Tuple + " is higher than arg2Tuple=" + arg2Tuple);
+
+          }
+
+          // System.out.println();
+        }
+      }
+    }
+
+    // if a parameter has a composite location and the first element of the parameter location
+    // matches the callee's 'this'
+    // we have a more specific constraint: the caller's corresponding argument is higher than the
+    // parameter location which is translated into the caller
+
+    for (int idx = 0; idx < numParam; idx++) {
+      FlowNode paramNode = calleeFlowGraph.getParamFlowNode(idx);
+      CompositeLocation compLoc = paramNode.getCompositeLocation();
+      // System.out.println("paramNode=" + paramNode + "   compLoc=" + compLoc);
+      if (compLoc != null && compLoc.get(0).getLocDescriptor().equals(min.getMethod().getThis())) {
+        // System.out.println("$$$COMPLOC CASE=" + compLoc + "  idx=" + idx);
+
+        NTuple<Descriptor> argTuple = getNodeTupleByArgIdx(min, idx);
+        // System.out.println("--- argTuple=" + argTuple + " current compLoc="
+        // + callerFlowGraph.getFlowNode(argTuple).getCompositeLocation());
+
+        NTuple<Descriptor> translatedParamTuple =
+            translateCompositeLocationToCaller(idx, min, compLoc);
+        // System.out.println("add a flow edge= " + argTuple + "->" + translatedParamTuple);
+        callerFlowGraph.addValueFlowEdge(argTuple, translatedParamTuple);
+
+        Set<NTuple<Location>> pcLocTupleSet = getPCLocTupleSet(min);
+        for (Iterator iterator = pcLocTupleSet.iterator(); iterator.hasNext();) {
+          NTuple<Location> pcLocTuple = (NTuple<Location>) iterator.next();
+          callerFlowGraph.addValueFlowEdge(translateToDescTuple(pcLocTuple), translatedParamTuple);
+        }
+
+      }
+    }
+
+  }
+
+  private boolean containsPrefix(Descriptor prefixDesc, Set<FlowNode> set) {
+
+    for (Iterator iterator = set.iterator(); iterator.hasNext();) {
+      FlowNode flowNode = (FlowNode) iterator.next();
+      if (flowNode.getDescTuple().startsWith(prefixDesc)) {
+        // System.out.println("FOUND=" + flowNode);
+        return true;
+      }
+    }
+    return false;
+  }
+
+  private NTuple<Descriptor> translateCompositeLocationToCaller(int idx, MethodInvokeNode min,
+      CompositeLocation compLocForParam1) {
+
+    NTuple<Descriptor> baseTuple = mapMethodInvokeNodeToBaseTuple.get(min);
+
+    NTuple<Descriptor> tuple = new NTuple<Descriptor>();
+    for (int i = 0; i < baseTuple.size(); i++) {
+      tuple.add(baseTuple.get(i));
+    }
+
+    for (int i = 1; i < compLocForParam1.getSize(); i++) {
+      Location loc = compLocForParam1.get(i);
+      tuple.add(loc.getLocDescriptor());
+    }
+
+    return tuple;
+  }
+
+  private CompositeLocation generateCompositeLocation(NTuple<Location> prefixLocTuple) {
+
+    // System.out.println("generateCompositeLocation=" + prefixLocTuple);
+
+    CompositeLocation newCompLoc = new CompositeLocation();
+    for (int i = 0; i < prefixLocTuple.size(); i++) {
+      newCompLoc.addLocation(prefixLocTuple.get(i));
+    }
+
+    Descriptor lastDescOfPrefix = prefixLocTuple.get(prefixLocTuple.size() - 1).getLocDescriptor();
+
+    ClassDescriptor enclosingDescriptor;
+    if (lastDescOfPrefix instanceof FieldDescriptor) {
+      enclosingDescriptor = ((FieldDescriptor) lastDescOfPrefix).getType().getClassDesc();
+      // System.out.println("enclosingDescriptor0=" + enclosingDescriptor);
+    } else if (lastDescOfPrefix.equals(GLOBALDESC)) {
+      MethodDescriptor currentMethodDesc = (MethodDescriptor) prefixLocTuple.get(0).getDescriptor();
+      enclosingDescriptor = currentMethodDesc.getClassDesc();
+    } else {
+      // var descriptor case
+      enclosingDescriptor = ((VarDescriptor) lastDescOfPrefix).getType().getClassDesc();
+    }
+    // System.out.println("enclosingDescriptor=" + enclosingDescriptor);
+
+    LocationDescriptor newLocDescriptor = generateNewLocationDescriptor();
+    newLocDescriptor.setEnclosingClassDesc(enclosingDescriptor);
+
+    Location newLoc = new Location(enclosingDescriptor, newLocDescriptor.getSymbol());
+    newLoc.setLocDescriptor(newLocDescriptor);
+    newCompLoc.addLocation(newLoc);
+
+    // System.out.println("--newCompLoc=" + newCompLoc);
+    return newCompLoc;
+  }
+
+  private CompositeLocation generateCompositeLocation(MethodDescriptor md,
+      NTuple<Descriptor> paramPrefix) {
+
+    // System.out.println("generateCompositeLocation=" + paramPrefix);
+
+    CompositeLocation newCompLoc = convertToCompositeLocation(md, paramPrefix);
+
+    Descriptor lastDescOfPrefix = paramPrefix.get(paramPrefix.size() - 1);
+    // System.out.println("lastDescOfPrefix=" + lastDescOfPrefix + "  kind="
+    // + lastDescOfPrefix.getClass());
+    ClassDescriptor enclosingDescriptor;
+    if (lastDescOfPrefix instanceof FieldDescriptor) {
+      enclosingDescriptor = ((FieldDescriptor) lastDescOfPrefix).getType().getClassDesc();
+      // System.out.println("enclosingDescriptor0=" + enclosingDescriptor);
+    } else {
+      // var descriptor case
+      enclosingDescriptor = ((VarDescriptor) lastDescOfPrefix).getType().getClassDesc();
+    }
+    // System.out.println("enclosingDescriptor=" + enclosingDescriptor);
+
+    LocationDescriptor newLocDescriptor = generateNewLocationDescriptor();
+    newLocDescriptor.setEnclosingClassDesc(enclosingDescriptor);
+
+    Location newLoc = new Location(enclosingDescriptor, newLocDescriptor.getSymbol());
+    newLoc.setLocDescriptor(newLocDescriptor);
+    newCompLoc.addLocation(newLoc);
+
+    // System.out.println("--newCompLoc=" + newCompLoc);
+    return newCompLoc;
+  }
+
+  private List<NTuple<Descriptor>> translatePrefixListToCallee(Descriptor baseRef,
+      MethodDescriptor mdCallee, List<NTuple<Descriptor>> callerPrefixList) {
+
+    List<NTuple<Descriptor>> calleePrefixList = new ArrayList<NTuple<Descriptor>>();
+
+    for (int i = 0; i < callerPrefixList.size(); i++) {
+      NTuple<Descriptor> prefix = callerPrefixList.get(i);
+      if (prefix.startsWith(baseRef)) {
+        NTuple<Descriptor> calleePrefix = new NTuple<Descriptor>();
+        calleePrefix.add(mdCallee.getThis());
+        for (int k = 1; k < prefix.size(); k++) {
+          calleePrefix.add(prefix.get(k));
+        }
+        calleePrefixList.add(calleePrefix);
+      }
+    }
+
+    return calleePrefixList;
+
+  }
+
+  public CompositeLocation convertToCompositeLocation(MethodDescriptor md, NTuple<Descriptor> tuple) {
+
+    CompositeLocation compLoc = new CompositeLocation();
+
+    Descriptor enclosingDescriptor = md;
+
+    for (int i = 0; i < tuple.size(); i++) {
+      Descriptor curDescriptor = tuple.get(i);
+      Location locElement = new Location(enclosingDescriptor, curDescriptor.getSymbol());
+      locElement.setLocDescriptor(curDescriptor);
+      compLoc.addLocation(locElement);
+
+      if (curDescriptor instanceof VarDescriptor) {
+        enclosingDescriptor = md.getClassDesc();
+      } else if (curDescriptor instanceof FieldDescriptor) {
+        enclosingDescriptor = ((FieldDescriptor) curDescriptor).getClassDescriptor();
+      } else if (curDescriptor instanceof NameDescriptor) {
+        // it is "GLOBAL LOC" case!
+        enclosingDescriptor = GLOBALDESC;
+      } else if (curDescriptor instanceof InterDescriptor) {
+        enclosingDescriptor = getFlowGraph(md).getEnclosingDescriptor(curDescriptor);
+      } else {
+        enclosingDescriptor = null;
+      }
+
+    }
+
+    return compLoc;
+  }
+
+  private LocationDescriptor generateNewLocationDescriptor() {
+    return new LocationDescriptor("Loc" + (locSeed++));
+  }
+
+  private int getPrefixIndex(NTuple<Descriptor> tuple1, NTuple<Descriptor> tuple2) {
+
+    // return the index where the prefix shared by tuple1 and tuple2 is ended
+    // if there is no prefix shared by both of them, return -1
+
+    int minSize = tuple1.size();
+    if (minSize > tuple2.size()) {
+      minSize = tuple2.size();
+    }
+
+    int idx = -1;
+    for (int i = 0; i < minSize; i++) {
+      if (!tuple1.get(i).equals(tuple2.get(i))) {
+        break;
+      } else {
+        idx++;
+      }
     }
 
+    return idx;
   }
 
-  private void propagateRelationToCaller(MethodInvokeNode min, MethodDescriptor mdCaller,
-      MethodDescriptor possibleMdCallee) {
-
-    SSJavaLattice<String> calleeLattice = getMethodLattice(possibleMdCallee);
-
-    FlowGraph calleeFlowGraph = getFlowGraph(possibleMdCallee);
+  private CompositeLocation generateInferredCompositeLocation(MethodLocationInfo methodInfo,
+      NTuple<Location> tuple) {
 
-    // find parameter node
-    Set<FlowNode> paramNodeSet = calleeFlowGraph.getParameterNodeSet();
+    // first, retrieve inferred location by the local var descriptor
+    CompositeLocation inferLoc = new CompositeLocation();
 
-    for (Iterator iterator = paramNodeSet.iterator(); iterator.hasNext();) {
-      FlowNode paramFlowNode1 = (FlowNode) iterator.next();
-
-      for (Iterator iterator2 = paramNodeSet.iterator(); iterator2.hasNext();) {
-        FlowNode paramFlowNode2 = (FlowNode) iterator2.next();
-
-        String paramSymbol1 = getSymbol(0, paramFlowNode1);
-        String paramSymbol2 = getSymbol(0, paramFlowNode2);
-        // if two parameters have a relation, we need to propagate this relation
-        // to the caller
-        if (!(paramSymbol1.equals(paramSymbol2))
-            && calleeLattice.isComparable(paramSymbol1, paramSymbol2)) {
-          int higherLocIdxCallee;
-          int lowerLocIdxCallee;
-          if (calleeLattice.isGreaterThan(paramSymbol1, paramSymbol2)) {
-            higherLocIdxCallee = calleeFlowGraph.getParamIdx(paramFlowNode1.getDescTuple());
-            lowerLocIdxCallee = calleeFlowGraph.getParamIdx(paramFlowNode2.getDescTuple());
-          } else {
-            higherLocIdxCallee = calleeFlowGraph.getParamIdx(paramFlowNode2.getDescTuple());
-            lowerLocIdxCallee = calleeFlowGraph.getParamIdx(paramFlowNode1.getDescTuple());
-          }
+    CompositeLocation localVarInferLoc =
+        methodInfo.getInferLocation(tuple.get(0).getLocDescriptor());
 
-          NTuple<Descriptor> higherArg = getArgTupleByArgIdx(min, higherLocIdxCallee);
-          NTuple<Descriptor> lowerArg = getArgTupleByArgIdx(min, lowerLocIdxCallee);
+    localVarInferLoc.get(0).setLocDescriptor(tuple.get(0).getLocDescriptor());
 
-          addFlowGraphEdge(mdCaller, higherArg, lowerArg);
+    for (int i = 0; i < localVarInferLoc.getSize(); i++) {
+      inferLoc.addLocation(localVarInferLoc.get(i));
+    }
 
-        }
+    for (int i = 1; i < tuple.size(); i++) {
+      Location cur = tuple.get(i);
+      Descriptor enclosingDesc = cur.getDescriptor();
+      Descriptor curDesc = cur.getLocDescriptor();
 
+      Location inferLocElement;
+      if (curDesc == null) {
+        // in this case, we have a newly generated location.
+        inferLocElement = new Location(enclosingDesc, cur.getLocIdentifier());
+      } else {
+        String fieldLocSymbol =
+            getLocationInfo(enclosingDesc).getInferLocation(curDesc).get(0).getLocIdentifier();
+        inferLocElement = new Location(enclosingDesc, fieldLocSymbol);
+        inferLocElement.setLocDescriptor(curDesc);
       }
 
+      inferLoc.addLocation(inferLocElement);
+
     }
 
+    assert (inferLoc.get(0).getLocDescriptor().getSymbol() == inferLoc.get(0).getLocIdentifier());
+    return inferLoc;
+  }
+
+  public LocationInfo getLocationInfo(Descriptor d) {
+    if (d instanceof MethodDescriptor) {
+      return getMethodLocationInfo((MethodDescriptor) d);
+    } else {
+      return getFieldLocationInfo((ClassDescriptor) d);
+    }
   }
 
   private MethodLocationInfo getMethodLocationInfo(MethodDescriptor md) {
 
-    if (!mapLatticeToMethodLocationInfo.containsKey(md)) {
-      mapLatticeToMethodLocationInfo.put(md, new MethodLocationInfo(md));
+    if (!mapMethodDescToMethodLocationInfo.containsKey(md)) {
+      mapMethodDescToMethodLocationInfo.put(md, new MethodLocationInfo(md));
     }
 
-    return mapLatticeToMethodLocationInfo.get(md);
+    return mapMethodDescToMethodLocationInfo.get(md);
 
   }
 
-  private void addRelationToLattice(MethodDescriptor md, SSJavaLattice<String> methodLattice,
-      FlowNode srcNode, FlowNode dstNode) {
+  private LocationInfo getFieldLocationInfo(ClassDescriptor cd) {
 
-    // add a new binary relation of dstNode < srcNode
-    String srcSymbol = getSymbol(0, srcNode);
-    String dstSymbol = getSymbol(0, dstNode);
+    if (!mapClassToLocationInfo.containsKey(cd)) {
+      mapClassToLocationInfo.put(cd, new LocationInfo(cd));
+    }
 
-    FlowGraph flowGraph = getFlowGraph(md);
-    MethodLocationInfo methodInfo = getMethodLocationInfo(md);
+    return mapClassToLocationInfo.get(cd);
 
-    if (srcNode.isParameter()) {
-      int paramIdx = flowGraph.getParamIdx(srcNode.getDescTuple());
-      methodInfo.addParameter(srcSymbol, srcNode, paramIdx);
-    }
-    if (dstNode.isParameter()) {
-      int paramIdx = flowGraph.getParamIdx(dstNode.getDescTuple());
-      methodInfo.addParameter(dstSymbol, dstNode, paramIdx);
+  }
+
+  private void addPrefixMapping(Map<NTuple<Location>, Set<NTuple<Location>>> map,
+      NTuple<Location> prefix, NTuple<Location> element) {
+
+    if (!map.containsKey(prefix)) {
+      map.put(prefix, new HashSet<NTuple<Location>>());
     }
+    map.get(prefix).add(element);
+  }
+
+  private boolean containsNonPrimitiveElement(Set<Descriptor> descSet) {
+    for (Iterator iterator = descSet.iterator(); iterator.hasNext();) {
+      Descriptor desc = (Descriptor) iterator.next();
+
+      if (desc.equals(LocationInference.GLOBALDESC)) {
+        return true;
+      } else if (desc instanceof VarDescriptor) {
+        if (!((VarDescriptor) desc).getType().isPrimitive()) {
+          return true;
+        }
+      } else if (desc instanceof FieldDescriptor) {
+        if (!((FieldDescriptor) desc).getType().isPrimitive()) {
+          return true;
+        }
+      }
 
-    if (!methodLattice.isGreaterThan(srcSymbol, dstSymbol)) {
-      // if the lattice does not have this relation, add it
-      methodLattice.addRelationHigherToLower(srcSymbol, dstSymbol);
     }
+    return false;
+  }
 
+  public SSJavaLattice<String> getLattice(Descriptor d) {
+    if (d instanceof MethodDescriptor) {
+      return getMethodLattice((MethodDescriptor) d);
+    } else {
+      return getFieldLattice((ClassDescriptor) d);
+    }
   }
 
   private SSJavaLattice<String> getMethodLattice(MethodDescriptor md) {
@@ -519,38 +4812,49 @@ public class LocationInference {
     md2lattice.put(md, lattice);
   }
 
-  private void extractRelationFromFieldFlows(ClassDescriptor cd, FlowNode srcNode,
-      FlowNode dstNode, int idx) {
+  private void extractFlowsBetweenFields(ClassDescriptor cd, FlowNode srcNode, FlowNode dstNode,
+      int idx) {
+
+    NTuple<Descriptor> srcCurTuple = srcNode.getCurrentDescTuple();
+    NTuple<Descriptor> dstCurTuple = dstNode.getCurrentDescTuple();
 
-    if (srcNode.getDescTuple().get(idx).equals(dstNode.getDescTuple().get(idx))
-        && srcNode.getDescTuple().size() > (idx + 1) && dstNode.getDescTuple().size() > (idx + 1)) {
+    if (srcCurTuple.get(idx).equals(dstCurTuple.get(idx)) && srcCurTuple.size() > (idx + 1)
+        && dstCurTuple.size() > (idx + 1)) {
       // value flow between fields: we don't need to add a binary relation
       // for this case
 
-      Descriptor desc = srcNode.getDescTuple().get(idx);
+      Descriptor desc = srcCurTuple.get(idx);
       ClassDescriptor classDesc;
 
       if (idx == 0) {
         classDesc = ((VarDescriptor) desc).getType().getClassDesc();
       } else {
-        classDesc = ((FieldDescriptor) desc).getType().getClassDesc();
+        if (desc instanceof FieldDescriptor) {
+          classDesc = ((FieldDescriptor) desc).getType().getClassDesc();
+        } else {
+          // this case is that the local variable has a composite location assignment
+          // the following element after the composite location to the local variable
+          // has the enclosing descriptor of the local variable
+          Descriptor localDesc = srcNode.getDescTuple().get(0);
+          classDesc = ((VarDescriptor) localDesc).getType().getClassDesc();
+        }
       }
-
-      extractRelationFromFieldFlows(classDesc, srcNode, dstNode, idx + 1);
+      extractFlowsBetweenFields(classDesc, srcNode, dstNode, idx + 1);
 
     } else {
 
-      Descriptor srcFieldDesc = srcNode.getDescTuple().get(idx);
-      Descriptor dstFieldDesc = dstNode.getDescTuple().get(idx);
-
-      // add a new binary relation of dstNode < srcNode
-      SSJavaLattice<String> fieldLattice = getFieldLattice(cd);
-
-      String srcSymbol = srcFieldDesc.getSymbol();
-      String dstSymbol = dstFieldDesc.getSymbol();
-
-      if (!fieldLattice.isGreaterThan(srcSymbol, dstSymbol)) {
-        fieldLattice.addRelationHigherToLower(srcSymbol, dstSymbol);
+      Descriptor srcFieldDesc = srcCurTuple.get(idx);
+      Descriptor dstFieldDesc = dstCurTuple.get(idx);
+
+      // System.out.println("srcFieldDesc=" + srcFieldDesc + "  dstFieldDesc=" + dstFieldDesc
+      // + "   idx=" + idx);
+      if (!srcFieldDesc.equals(dstFieldDesc)) {
+        // add a new edge
+        // System.out.println("-ADD EDGE");
+        getHierarchyGraph(cd).addEdge(srcFieldDesc, dstFieldDesc);
+      } else if (!isReference(srcFieldDesc) && !isReference(dstFieldDesc)) {
+        // System.out.println("-ADD EDGE");
+        getHierarchyGraph(cd).addEdge(srcFieldDesc, dstFieldDesc);
       }
 
     }
@@ -564,21 +4868,30 @@ public class LocationInference {
     return cd2lattice.get(cd);
   }
 
-  public void constructFlowGraph() {
+  public LinkedList<MethodDescriptor> computeMethodList() {
+
+    Set<MethodDescriptor> toSort = new HashSet<MethodDescriptor>();
 
     setupToAnalyze();
 
+    Set<MethodDescriptor> visited = new HashSet<MethodDescriptor>();
+    Set<MethodDescriptor> reachableCallee = new HashSet<MethodDescriptor>();
+
     while (!toAnalyzeIsEmpty()) {
       ClassDescriptor cd = toAnalyzeNext();
 
+      if (cd.getClassName().equals("Object")) {
+        rootClassDescriptor = cd;
+        // inheritanceTree = new InheritanceTree<ClassDescriptor>(cd);
+      }
+
       setupToAnalazeMethod(cd);
+      temp_toanalyzeMethodList.removeAll(visited);
+
       while (!toAnalyzeMethodIsEmpty()) {
         MethodDescriptor md = toAnalyzeMethodNext();
-        if (ssjava.needTobeAnnotated(md)) {
-          if (state.SSJAVADEBUG) {
-            System.out.println();
-            System.out.println("SSJAVA: Constructing a flow graph: " + md);
-          }
+        if ((!visited.contains(md))
+            && (ssjava.needTobeAnnotated(md) || reachableCallee.contains(md))) {
 
           // creates a mapping from a method descriptor to virtual methods
           Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
@@ -587,25 +4900,213 @@ public class LocationInference {
           } else {
             setPossibleCallees.addAll(ssjava.getCallGraph().getMethods(md));
           }
-          mapMethodDescToPossibleMethodDescSet.put(md, setPossibleCallees);
 
-          // creates a mapping from a parameter descriptor to its index
-          Map<Descriptor, Integer> mapParamDescToIdx = new HashMap<Descriptor, Integer>();
-          int offset = md.isStatic() ? 0 : 1;
-          for (int i = 0; i < md.numParameters(); i++) {
-            Descriptor paramDesc = (Descriptor) md.getParameter(i);
-            mapParamDescToIdx.put(paramDesc, new Integer(i + offset));
+          Set<MethodDescriptor> calleeSet = ssjava.getCallGraph().getCalleeSet(md);
+          Set<MethodDescriptor> needToAnalyzeCalleeSet = new HashSet<MethodDescriptor>();
+
+          for (Iterator iterator = calleeSet.iterator(); iterator.hasNext();) {
+            MethodDescriptor calleemd = (MethodDescriptor) iterator.next();
+            if ((!ssjava.isTrustMethod(calleemd))
+                && (!ssjava.isSSJavaUtil(calleemd.getClassDesc()))
+                && (!calleemd.getModifiers().isNative())) {
+              if (!visited.contains(calleemd)) {
+                temp_toanalyzeMethodList.add(calleemd);
+              }
+              reachableCallee.add(calleemd);
+              needToAnalyzeCalleeSet.add(calleemd);
+            }
           }
 
-          FlowGraph fg = new FlowGraph(md, mapParamDescToIdx);
-          mapMethodDescriptorToFlowGraph.put(md, fg);
+          mapMethodToCalleeSet.put(md, needToAnalyzeCalleeSet);
+
+          visited.add(md);
+
+          toSort.add(md);
+        }
+      }
+    }
+
+    return ssjava.topologicalSort(toSort);
+
+  }
+
+  public boolean isTransitivelyCalledFrom(MethodDescriptor callee, MethodDescriptor caller) {
+    // if the callee is transitively invoked from the caller
+    // return true;
+
+    int callerIdx = toanalyze_methodDescList.indexOf(caller);
+    int calleeIdx = toanalyze_methodDescList.indexOf(callee);
+
+    if (callerIdx < calleeIdx) {
+      return true;
+    }
+
+    return false;
+
+  }
+
+  public void constructFlowGraph() {
+
+    System.out.println("");
+    toanalyze_methodDescList = computeMethodList();
+
+    // hack... it seems that there is a problem with topological sorting.
+    // so String.toString(Object o) is appeared too higher in the call chain.
+    MethodDescriptor mdToString1 = null;
+    MethodDescriptor mdToString2 = null;
+    for (Iterator iterator = toanalyze_methodDescList.iterator(); iterator.hasNext();) {
+      MethodDescriptor md = (MethodDescriptor) iterator.next();
+      if (md.toString().equals("public static String String.valueOf(Object o)")) {
+        mdToString1 = md;
+      }
+      if (md.toString().equals("public String Object.toString()")) {
+        mdToString2 = md;
+      }
+    }
+
+    if (mdToString1 != null) {
+      toanalyze_methodDescList.remove(mdToString1);
+      toanalyze_methodDescList.addLast(mdToString1);
+    }
+    if (mdToString2 != null) {
+      toanalyze_methodDescList.remove(mdToString2);
+      toanalyze_methodDescList.addLast(mdToString2);
+    }
+
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    // System.out.println("@@@methodDescList=" + methodDescList);
+    // System.exit(0);
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+      if (state.SSJAVADEBUG) {
+        System.out.println();
+        System.out.println("SSJAVA: Constructing a flow graph: " + md);
+
+        // creates a mapping from a parameter descriptor to its index
+        Map<Descriptor, Integer> mapParamDescToIdx = new HashMap<Descriptor, Integer>();
+        int offset = 0;
+        if (!md.isStatic()) {
+          offset = 1;
+          mapParamDescToIdx.put(md.getThis(), 0);
+        }
+
+        for (int i = 0; i < md.numParameters(); i++) {
+          Descriptor paramDesc = (Descriptor) md.getParameter(i);
+          mapParamDescToIdx.put(paramDesc, new Integer(i + offset));
+        }
+
+        FlowGraph fg = new FlowGraph(md, mapParamDescToIdx);
+        mapMethodDescriptorToFlowGraph.put(md, fg);
+
+        analyzeMethodBody(md.getClassDesc(), md);
+
+        // System.out.println("##constructSubGlobalFlowGraph");
+        // GlobalFlowGraph subGlobalFlowGraph = constructSubGlobalFlowGraph(fg);
+        // mapMethodDescriptorToSubGlobalFlowGraph.put(md, subGlobalFlowGraph);
+        //
+        // // TODO
+        // System.out.println("##addValueFlowsFromCalleeSubGlobalFlowGraph");
+        // addValueFlowsFromCalleeSubGlobalFlowGraph(md, subGlobalFlowGraph);
+        // subGlobalFlowGraph.writeGraph("_SUBGLOBAL");
+        //
+        // propagateFlowsFromCalleesWithNoCompositeLocation(md);
+      }
+    }
+    // _debug_printGraph();
+
+  }
+
+  private void constructGlobalFlowGraph() {
+    LinkedList<MethodDescriptor> methodDescList =
+        (LinkedList<MethodDescriptor>) toanalyze_methodDescList.clone();
+
+    while (!methodDescList.isEmpty()) {
+      MethodDescriptor md = methodDescList.removeLast();
+      if (state.SSJAVADEBUG) {
+        System.out.println();
+        System.out.println("SSJAVA: Constructing a sub global flow graph: " + md);
+
+        constructSubGlobalFlowGraph(getFlowGraph(md));
+
+        // TODO
+        // System.out.println("-add Value Flows From CalleeSubGlobalFlowGraph");
+        addValueFlowsFromCalleeSubGlobalFlowGraph(md);
+        // subGlobalFlowGraph.writeGraph("_SUBGLOBAL");
+
+        // System.out.println("-propagate Flows From Callees With No CompositeLocation");
+        // propagateFlowsFromCalleesWithNoCompositeLocation(md);
+
+        // mark if a parameter has incoming flows
+        checkParamNodesInSubGlobalFlowGraph(md);
+
+      }
+    }
+  }
+
+  private void checkParamNodesInSubGlobalFlowGraph(MethodDescriptor md) {
+    GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+    FlowGraph flowGraph = getFlowGraph(md);
+
+    Set<FlowNode> paramFlowNodeSet = flowGraph.getParamFlowNodeSet();
+    for (Iterator iterator = paramFlowNodeSet.iterator(); iterator.hasNext();) {
+      FlowNode paramFlowNode = (FlowNode) iterator.next();
+      // System.out.println("paramFlowNode=" + paramFlowNode);
+      NTuple<Descriptor> paramDescTuple = paramFlowNode.getDescTuple();
+      NTuple<Location> paramLocTuple = translateToLocTuple(md, paramDescTuple);
+      GlobalFlowNode paramGlobalNode = globalFlowGraph.getFlowNode(paramLocTuple);
+
+      Set<GlobalFlowNode> incomingNodeSet =
+          globalFlowGraph.getIncomingNodeSetByPrefix(paramLocTuple.get(0));
+
+      if (incomingNodeSet.size() > 0) {
+        paramGlobalNode.setParamNodeWithIncomingFlows(true);
+      }
+
+    }
+  }
+
+  private Set<MethodInvokeNode> getMethodInvokeNodeSet(MethodDescriptor md) {
+    if (!mapMethodDescriptorToMethodInvokeNodeSet.containsKey(md)) {
+      mapMethodDescriptorToMethodInvokeNodeSet.put(md, new HashSet<MethodInvokeNode>());
+    }
+    return mapMethodDescriptorToMethodInvokeNodeSet.get(md);
+  }
+
+  private void propagateFlowsFromCalleesWithNoCompositeLocation(MethodDescriptor mdCaller) {
+
+    // the transformation for a call site propagates flows through parameters
+    // if the method is virtual, it also grab all relations from any possible
+    // callees
+
+    Set<MethodInvokeNode> setMethodInvokeNode =
+        mapMethodDescriptorToMethodInvokeNodeSet.get(mdCaller);
+
+    if (setMethodInvokeNode != null) {
+
+      for (Iterator iterator = setMethodInvokeNode.iterator(); iterator.hasNext();) {
+        MethodInvokeNode min = (MethodInvokeNode) iterator.next();
+        MethodDescriptor mdCallee = min.getMethod();
+        Set<MethodDescriptor> setPossibleCallees = new HashSet<MethodDescriptor>();
+        if (mdCallee.isStatic()) {
+          setPossibleCallees.add(mdCallee);
+        } else {
+          Set<MethodDescriptor> calleeSet = ssjava.getCallGraph().getMethods(mdCallee);
+          // removes method descriptors that are not invoked by the caller
+          calleeSet.retainAll(mapMethodToCalleeSet.get(mdCaller));
+          setPossibleCallees.addAll(calleeSet);
+        }
 
-          analyzeMethodBody(cd, md);
+        for (Iterator iterator2 = setPossibleCallees.iterator(); iterator2.hasNext();) {
+          MethodDescriptor possibleMdCallee = (MethodDescriptor) iterator2.next();
+          propagateFlowsToCallerWithNoCompositeLocation(min, mdCaller, possibleMdCallee);
         }
+
       }
     }
 
-    _debug_printGraph();
   }
 
   private void analyzeMethodBody(ClassDescriptor cd, MethodDescriptor md) {
@@ -657,16 +5158,50 @@ public class LocationInference {
       break;
 
     case Kind.SwitchStatementNode:
-      analyzeSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn);
+      analyzeSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn, implicitFlowTupleSet);
       break;
 
     }
 
   }
 
+  private void analyzeSwitchBlockNode(MethodDescriptor md, SymbolTable nametable,
+      SwitchBlockNode sbn, NodeTupleSet implicitFlowTupleSet) {
+
+    analyzeFlowBlockNode(md, nametable, sbn.getSwitchBlockStatement(), implicitFlowTupleSet);
+
+  }
+
   private void analyzeSwitchStatementNode(MethodDescriptor md, SymbolTable nametable,
-      SwitchStatementNode bsn) {
-    // TODO Auto-generated method stub
+      SwitchStatementNode ssn, NodeTupleSet implicitFlowTupleSet) {
+
+    NodeTupleSet condTupleNode = new NodeTupleSet();
+    analyzeFlowExpressionNode(md, nametable, ssn.getCondition(), condTupleNode, null,
+        implicitFlowTupleSet, false);
+
+    NodeTupleSet newImplicitTupleSet = new NodeTupleSet();
+
+    newImplicitTupleSet.addTupleSet(implicitFlowTupleSet);
+    newImplicitTupleSet.addTupleSet(condTupleNode);
+
+    if (needToGenerateInterLoc(newImplicitTupleSet)) {
+      // need to create an intermediate node for the GLB of conditional
+      // locations & implicit flows
+
+      NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      for (Iterator<NTuple<Descriptor>> idxIter = newImplicitTupleSet.iterator(); idxIter.hasNext();) {
+        NTuple<Descriptor> tuple = idxIter.next();
+        addFlowGraphEdge(md, tuple, interTuple);
+      }
+      newImplicitTupleSet.clear();
+      newImplicitTupleSet.addTuple(interTuple);
+    }
+
+    BlockNode sbn = ssn.getSwitchBody();
+    for (int i = 0; i < sbn.size(); i++) {
+      analyzeSwitchBlockNode(md, nametable, (SwitchBlockNode) sbn.get(i), newImplicitTupleSet);
+    }
+
   }
 
   private void analyzeFlowSubBlockNode(MethodDescriptor md, SymbolTable nametable,
@@ -677,23 +5212,91 @@ public class LocationInference {
   private void analyzeFlowReturnNode(MethodDescriptor md, SymbolTable nametable, ReturnNode rn,
       NodeTupleSet implicitFlowTupleSet) {
 
+    // System.out.println("-analyzeFlowReturnNode=" + rn.printNode(0));
     ExpressionNode returnExp = rn.getReturnExpression();
 
-    NodeTupleSet nodeSet = new NodeTupleSet();
-    analyzeFlowExpressionNode(md, nametable, returnExp, nodeSet, false);
+    if (returnExp != null) {
+      NodeTupleSet nodeSet = new NodeTupleSet();
+      // if a return expression returns a literal value, nodeSet is empty
+      analyzeFlowExpressionNode(md, nametable, returnExp, nodeSet, false);
+      FlowGraph fg = getFlowGraph(md);
+
+      // if (implicitFlowTupleSet.size() == 1
+      // &&
+      // fg.getFlowNode(implicitFlowTupleSet.iterator().next()).isIntermediate())
+      // {
+      //
+      // // since there is already an intermediate node for the GLB of implicit
+      // flows
+      // // we don't need to create another intermediate node.
+      // // just re-use the intermediate node for implicit flows.
+      //
+      // FlowNode meetNode =
+      // fg.getFlowNode(implicitFlowTupleSet.iterator().next());
+      //
+      // for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
+      // NTuple<Descriptor> returnNodeTuple = (NTuple<Descriptor>)
+      // iterator.next();
+      // fg.addValueFlowEdge(returnNodeTuple, meetNode.getDescTuple());
+      // }
+      //
+      // }
+
+      NodeTupleSet currentFlowTupleSet = new NodeTupleSet();
 
-    FlowGraph fg = getFlowGraph(md);
+      // add tuples from return node
+      currentFlowTupleSet.addTupleSet(nodeSet);
 
-    // annotate the elements of the node set as the return location
-    for (Iterator iterator = nodeSet.iterator(); iterator.hasNext();) {
-      NTuple<Descriptor> returnDescTuple = (NTuple<Descriptor>) iterator.next();
-      fg.setReturnFlowNode(returnDescTuple);
-      for (Iterator iterator2 = implicitFlowTupleSet.iterator(); iterator2.hasNext();) {
-        NTuple<Descriptor> implicitFlowDescTuple = (NTuple<Descriptor>) iterator2.next();
-        fg.addValueFlowEdge(implicitFlowDescTuple, returnDescTuple);
+      // add tuples corresponding to the current implicit flows
+      currentFlowTupleSet.addTupleSet(implicitFlowTupleSet);
+
+      // System.out.println("---currentFlowTupleSet=" + currentFlowTupleSet);
+
+      if (needToGenerateInterLoc(currentFlowTupleSet)) {
+
+        FlowNode meetNode = fg.createIntermediateNode();
+        for (Iterator iterator = currentFlowTupleSet.iterator(); iterator.hasNext();) {
+          NTuple<Descriptor> currentFlowTuple = (NTuple<Descriptor>) iterator.next();
+          fg.addValueFlowEdge(currentFlowTuple, meetNode.getDescTuple());
+        }
+        fg.addReturnFlowNode(meetNode.getDescTuple());
+      } else {
+        // currentFlowTupleSet = removeLiteralTuple(currentFlowTupleSet);
+        for (Iterator iterator = currentFlowTupleSet.iterator(); iterator.hasNext();) {
+          NTuple<Descriptor> currentFlowTuple = (NTuple<Descriptor>) iterator.next();
+          fg.addReturnFlowNode(currentFlowTuple);
+        }
+      }
+
+    }
+
+  }
+
+  private NodeTupleSet removeLiteralTuple(NodeTupleSet inSet) {
+    NodeTupleSet tupleSet = new NodeTupleSet();
+    for (Iterator<NTuple<Descriptor>> iter = inSet.iterator(); iter.hasNext();) {
+      NTuple<Descriptor> tuple = iter.next();
+      if (!tuple.get(0).equals(LITERALDESC)) {
+        tupleSet.addTuple(tuple);
       }
     }
+    return tupleSet;
+  }
 
+  private boolean needToGenerateInterLoc(NodeTupleSet tupleSet) {
+    int size = 0;
+    for (Iterator<NTuple<Descriptor>> iter = tupleSet.iterator(); iter.hasNext();) {
+      NTuple<Descriptor> descTuple = iter.next();
+      if (!descTuple.get(0).equals(LITERALDESC)) {
+        size++;
+      }
+    }
+    if (size > 1) {
+      // System.out.println("needToGenerateInterLoc=" + tupleSet + "  size=" + size);
+      return true;
+    } else {
+      return false;
+    }
   }
 
   private void analyzeFlowLoopNode(MethodDescriptor md, SymbolTable nametable, LoopNode ln,
@@ -704,24 +5307,116 @@ public class LocationInference {
       NodeTupleSet condTupleNode = new NodeTupleSet();
       analyzeFlowExpressionNode(md, nametable, ln.getCondition(), condTupleNode, null,
           implicitFlowTupleSet, false);
-      condTupleNode.addTupleSet(implicitFlowTupleSet);
+
+      NodeTupleSet newImplicitTupleSet = new NodeTupleSet();
+
+      newImplicitTupleSet.addTupleSet(implicitFlowTupleSet);
+      newImplicitTupleSet.addTupleSet(condTupleNode);
+
+      newImplicitTupleSet.addGlobalFlowTupleSet(implicitFlowTupleSet.getGlobalLocTupleSet());
+      newImplicitTupleSet.addGlobalFlowTupleSet(condTupleNode.getGlobalLocTupleSet());
+
+      if (needToGenerateInterLoc(newImplicitTupleSet)) {
+        // need to create an intermediate node for the GLB of conditional
+        // locations & implicit flows
+
+        NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+        for (Iterator<NTuple<Descriptor>> idxIter = newImplicitTupleSet.iterator(); idxIter
+            .hasNext();) {
+          NTuple<Descriptor> tuple = idxIter.next();
+          addFlowGraphEdge(md, tuple, interTuple);
+        }
+        newImplicitTupleSet.clear();
+        newImplicitTupleSet.addTuple(interTuple);
+
+      }
+
+      // ///////////
+      // System.out.println("condTupleNode="+condTupleNode);
+      // NTuple<Descriptor> interTuple =
+      // getFlowGraph(md).createIntermediateNode().getDescTuple();
+      //
+      // for (Iterator<NTuple<Descriptor>> idxIter = condTupleNode.iterator();
+      // idxIter.hasNext();) {
+      // NTuple<Descriptor> tuple = idxIter.next();
+      // addFlowGraphEdge(md, tuple, interTuple);
+      // }
+
+      // for (Iterator<NTuple<Descriptor>> idxIter =
+      // implicitFlowTupleSet.iterator(); idxIter
+      // .hasNext();) {
+      // NTuple<Descriptor> tuple = idxIter.next();
+      // addFlowGraphEdge(md, tuple, interTuple);
+      // }
+
+      // NodeTupleSet newImplicitSet = new NodeTupleSet();
+      // newImplicitSet.addTuple(interTuple);
+      analyzeFlowBlockNode(md, nametable, ln.getBody(), newImplicitTupleSet);
+      // ///////////
+
+      // condTupleNode.addTupleSet(implicitFlowTupleSet);
 
       // add edges from condNodeTupleSet to all nodes of conditional nodes
-      analyzeFlowBlockNode(md, nametable, ln.getBody(), condTupleNode);
+      // analyzeFlowBlockNode(md, nametable, ln.getBody(), condTupleNode);
 
     } else {
       // check 'for loop' case
       BlockNode bn = ln.getInitializer();
-      analyzeFlowBlockNode(md, bn.getVarTable(), bn, implicitFlowTupleSet);
       bn.getVarTable().setParent(nametable);
+      for (int i = 0; i < bn.size(); i++) {
+        BlockStatementNode bsn = bn.get(i);
+        analyzeBlockStatementNode(md, bn.getVarTable(), bsn, implicitFlowTupleSet);
+      }
 
       NodeTupleSet condTupleNode = new NodeTupleSet();
       analyzeFlowExpressionNode(md, bn.getVarTable(), ln.getCondition(), condTupleNode, null,
           implicitFlowTupleSet, false);
-      condTupleNode.addTupleSet(implicitFlowTupleSet);
 
-      analyzeFlowBlockNode(md, bn.getVarTable(), ln.getUpdate(), condTupleNode);
-      analyzeFlowBlockNode(md, bn.getVarTable(), ln.getBody(), condTupleNode);
+      NodeTupleSet newImplicitTupleSet = new NodeTupleSet();
+      newImplicitTupleSet.addTupleSet(implicitFlowTupleSet);
+      newImplicitTupleSet.addTupleSet(condTupleNode);
+
+      if (needToGenerateInterLoc(newImplicitTupleSet)) {
+        // need to create an intermediate node for the GLB of conditional
+        // locations & implicit flows
+
+        NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+        for (Iterator<NTuple<Descriptor>> idxIter = newImplicitTupleSet.iterator(); idxIter
+            .hasNext();) {
+          NTuple<Descriptor> tuple = idxIter.next();
+          addFlowGraphEdge(md, tuple, interTuple);
+        }
+        newImplicitTupleSet.clear();
+        newImplicitTupleSet.addTuple(interTuple);
+
+      }
+
+      // ///////////
+      // NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      //
+      // for (Iterator<NTuple<Descriptor>> idxIter = condTupleNode.iterator(); idxIter.hasNext();) {
+      // NTuple<Descriptor> tuple = idxIter.next();
+      // addFlowGraphEdge(md, tuple, interTuple);
+      // }
+      //
+      // for (Iterator<NTuple<Descriptor>> idxIter = implicitFlowTupleSet.iterator(); idxIter
+      // .hasNext();) {
+      // NTuple<Descriptor> tuple = idxIter.next();
+      // addFlowGraphEdge(md, tuple, interTuple);
+      // }
+      //
+      // NodeTupleSet newImplicitSet = new NodeTupleSet();
+      // newImplicitSet.addTuple(interTuple);
+      analyzeFlowBlockNode(md, bn.getVarTable(), ln.getUpdate(), newImplicitTupleSet);
+      analyzeFlowBlockNode(md, bn.getVarTable(), ln.getBody(), newImplicitTupleSet);
+      // ///////////
+
+      // condTupleNode.addTupleSet(implicitFlowTupleSet);
+      //
+      // analyzeFlowBlockNode(md, bn.getVarTable(), ln.getUpdate(),
+      // condTupleNode);
+      // analyzeFlowBlockNode(md, bn.getVarTable(), ln.getBody(),
+      // condTupleNode);
 
     }
 
@@ -730,16 +5425,50 @@ public class LocationInference {
   private void analyzeFlowIfStatementNode(MethodDescriptor md, SymbolTable nametable,
       IfStatementNode isn, NodeTupleSet implicitFlowTupleSet) {
 
+    // System.out.println("analyzeFlowIfStatementNode=" + isn.printNode(0));
+
     NodeTupleSet condTupleNode = new NodeTupleSet();
     analyzeFlowExpressionNode(md, nametable, isn.getCondition(), condTupleNode, null,
         implicitFlowTupleSet, false);
 
-    // add edges from condNodeTupleSet to all nodes of conditional nodes
-    condTupleNode.addTupleSet(implicitFlowTupleSet);
-    analyzeFlowBlockNode(md, nametable, isn.getTrueBlock(), condTupleNode);
+    NodeTupleSet newImplicitTupleSet = new NodeTupleSet();
+
+    newImplicitTupleSet.addTupleSet(implicitFlowTupleSet);
+    newImplicitTupleSet.addTupleSet(condTupleNode);
+
+    // System.out.println("$$$GGGcondTupleNode=" + condTupleNode.getGlobalLocTupleSet());
+    // System.out.println("-condTupleNode=" + condTupleNode);
+    // System.out.println("-implicitFlowTupleSet=" + implicitFlowTupleSet);
+    // System.out.println("-newImplicitTupleSet=" + newImplicitTupleSet);
+
+    if (needToGenerateInterLoc(newImplicitTupleSet)) {
+
+      // need to create an intermediate node for the GLB of conditional locations & implicit flows
+      NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      for (Iterator<NTuple<Descriptor>> idxIter = newImplicitTupleSet.iterator(); idxIter.hasNext();) {
+        NTuple<Descriptor> tuple = idxIter.next();
+        addFlowGraphEdge(md, tuple, interTuple);
+      }
+      newImplicitTupleSet.clear();
+      newImplicitTupleSet.addTuple(interTuple);
+    }
+
+    // GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+    // for (Iterator<NTuple<Location>> iterator = condTupleNode.globalIterator();
+    // iterator.hasNext();) {
+    // NTuple<Location> calleeReturnLocTuple = iterator.next();
+    // for (Iterator<NTuple<Descriptor>> iter2 = newImplicitTupleSet.iterator(); iter2.hasNext();) {
+    // NTuple<Descriptor> callerImplicitTuple = iter2.next();
+    // globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple,
+    // translateToLocTuple(md, callerImplicitTuple));
+    // }
+    // }
+    newImplicitTupleSet.addGlobalFlowTupleSet(condTupleNode.getGlobalLocTupleSet());
+
+    analyzeFlowBlockNode(md, nametable, isn.getTrueBlock(), newImplicitTupleSet);
 
     if (isn.getFalseBlock() != null) {
-      analyzeFlowBlockNode(md, nametable, isn.getFalseBlock(), condTupleNode);
+      analyzeFlowBlockNode(md, nametable, isn.getFalseBlock(), newImplicitTupleSet);
     }
 
   }
@@ -748,22 +5477,55 @@ public class LocationInference {
       DeclarationNode dn, NodeTupleSet implicitFlowTupleSet) {
 
     VarDescriptor vd = dn.getVarDescriptor();
+    mapDescToDefinitionLine.put(vd, dn.getNumLine());
     NTuple<Descriptor> tupleLHS = new NTuple<Descriptor>();
     tupleLHS.add(vd);
-    getFlowGraph(md).createNewFlowNode(tupleLHS);
+    FlowNode fn = getFlowGraph(md).createNewFlowNode(tupleLHS);
+    fn.setDeclarationNode();
 
     if (dn.getExpression() != null) {
+      // System.out.println("-analyzeFlowDeclarationNode=" + dn.printNode(0));
 
-      NodeTupleSet tupleSetRHS = new NodeTupleSet();
-      analyzeFlowExpressionNode(md, nametable, dn.getExpression(), tupleSetRHS, null,
+      NodeTupleSet nodeSetRHS = new NodeTupleSet();
+      analyzeFlowExpressionNode(md, nametable, dn.getExpression(), nodeSetRHS, null,
           implicitFlowTupleSet, false);
 
-      // add a new flow edge from rhs to lhs
-      for (Iterator<NTuple<Descriptor>> iter = tupleSetRHS.iterator(); iter.hasNext();) {
-        NTuple<Descriptor> from = iter.next();
-        addFlowGraphEdge(md, from, tupleLHS);
+      // creates edges from RHS to LHS
+      NTuple<Descriptor> interTuple = null;
+      if (needToGenerateInterLoc(nodeSetRHS)) {
+        interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      }
+
+      for (Iterator<NTuple<Descriptor>> iter = nodeSetRHS.iterator(); iter.hasNext();) {
+        NTuple<Descriptor> fromTuple = iter.next();
+        // System.out.println("fromTuple=" + fromTuple + "  interTuple=" + interTuple + " tupleLSH="
+        // + tupleLHS);
+        addFlowGraphEdge(md, fromTuple, interTuple, tupleLHS);
+      }
+
+      // creates edges from implicitFlowTupleSet to LHS
+      for (Iterator<NTuple<Descriptor>> iter = implicitFlowTupleSet.iterator(); iter.hasNext();) {
+        NTuple<Descriptor> implicitTuple = iter.next();
+        addFlowGraphEdge(md, implicitTuple, tupleLHS);
+      }
+
+      GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+      for (Iterator<NTuple<Location>> iterator = nodeSetRHS.globalIterator(); iterator.hasNext();) {
+        NTuple<Location> calleeReturnLocTuple = iterator.next();
+
+        globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple, translateToLocTuple(md, tupleLHS));
+      }
+
+      for (Iterator<NTuple<Location>> iterator = implicitFlowTupleSet.globalIterator(); iterator
+          .hasNext();) {
+        NTuple<Location> implicitGlobalTuple = iterator.next();
+
+        globalFlowGraph.addValueFlowEdge(implicitGlobalTuple, translateToLocTuple(md, tupleLHS));
       }
 
+      // System.out.println("-nodeSetRHS=" + nodeSetRHS);
+      // System.out.println("-implicitFlowTupleSet=" + implicitFlowTupleSet);
+
     }
 
   }
@@ -783,30 +5545,34 @@ public class LocationInference {
       ExpressionNode en, NodeTupleSet nodeSet, NTuple<Descriptor> base,
       NodeTupleSet implicitFlowTupleSet, boolean isLHS) {
 
+    // System.out.println("en=" + en.printNode(0) + "   class=" + en.getClass());
+
     // note that expression node can create more than one flow node
     // nodeSet contains of flow nodes
     // base is always assigned to null except the case of a name node!
-
     NTuple<Descriptor> flowTuple;
-
     switch (en.kind()) {
-
     case Kind.AssignmentNode:
-      analyzeFlowAssignmentNode(md, nametable, (AssignmentNode) en, base, implicitFlowTupleSet);
+      analyzeFlowAssignmentNode(md, nametable, (AssignmentNode) en, nodeSet, base,
+          implicitFlowTupleSet);
       break;
 
     case Kind.FieldAccessNode:
       flowTuple =
           analyzeFlowFieldAccessNode(md, nametable, (FieldAccessNode) en, nodeSet, base,
-              implicitFlowTupleSet);
-      nodeSet.addTuple(flowTuple);
+              implicitFlowTupleSet, isLHS);
+      if (flowTuple != null) {
+        nodeSet.addTuple(flowTuple);
+      }
       return flowTuple;
 
     case Kind.NameNode:
       NodeTupleSet nameNodeSet = new NodeTupleSet();
       flowTuple =
           analyzeFlowNameNode(md, nametable, (NameNode) en, nameNodeSet, base, implicitFlowTupleSet);
-      nodeSet.addTuple(flowTuple);
+      if (flowTuple != null) {
+        nodeSet.addTuple(flowTuple);
+      }
       return flowTuple;
 
     case Kind.OpNode:
@@ -814,7 +5580,7 @@ public class LocationInference {
       break;
 
     case Kind.CreateObjectNode:
-      analyzeCreateObjectNode(md, nametable, (CreateObjectNode) en);
+      analyzeCreateObjectNode(md, nametable, (CreateObjectNode) en, nodeSet, implicitFlowTupleSet);
       break;
 
     case Kind.ArrayAccessNode:
@@ -822,11 +5588,12 @@ public class LocationInference {
       break;
 
     case Kind.LiteralNode:
-      analyzeLiteralNode(md, nametable, (LiteralNode) en);
+      analyzeFlowLiteralNode(md, nametable, (LiteralNode) en, nodeSet);
       break;
 
     case Kind.MethodInvokeNode:
-      analyzeFlowMethodInvokeNode(md, nametable, (MethodInvokeNode) en, implicitFlowTupleSet);
+      analyzeFlowMethodInvokeNode(md, nametable, (MethodInvokeNode) en, nodeSet,
+          implicitFlowTupleSet);
       break;
 
     case Kind.TertiaryNode:
@@ -834,9 +5601,8 @@ public class LocationInference {
       break;
 
     case Kind.CastNode:
-      analyzeFlowCastNode(md, nametable, (CastNode) en, implicitFlowTupleSet);
+      analyzeFlowCastNode(md, nametable, (CastNode) en, nodeSet, base, implicitFlowTupleSet);
       break;
-
     // case Kind.InstanceOfNode:
     // checkInstanceOfNode(md, nametable, (InstanceOfNode) en, td);
     // return null;
@@ -855,53 +5621,127 @@ public class LocationInference {
     // return null;
 
     }
+
     return null;
 
   }
 
   private void analyzeFlowCastNode(MethodDescriptor md, SymbolTable nametable, CastNode cn,
-      NodeTupleSet implicitFlowTupleSet) {
+      NodeTupleSet nodeSet, NTuple<Descriptor> base, NodeTupleSet implicitFlowTupleSet) {
 
-    NodeTupleSet nodeTupleSet = new NodeTupleSet();
-    analyzeFlowExpressionNode(md, nametable, cn.getExpression(), nodeTupleSet, false);
+    analyzeFlowExpressionNode(md, nametable, cn.getExpression(), nodeSet, base,
+        implicitFlowTupleSet, false);
 
   }
 
   private void analyzeFlowTertiaryNode(MethodDescriptor md, SymbolTable nametable, TertiaryNode tn,
       NodeTupleSet nodeSet, NodeTupleSet implicitFlowTupleSet) {
 
+    // System.out.println("analyzeFlowTertiaryNode=" + tn.printNode(0));
+
     NodeTupleSet tertiaryTupleNode = new NodeTupleSet();
     analyzeFlowExpressionNode(md, nametable, tn.getCond(), tertiaryTupleNode, null,
         implicitFlowTupleSet, false);
 
+    NodeTupleSet newImplicitTupleSet = new NodeTupleSet();
+    newImplicitTupleSet.addTupleSet(implicitFlowTupleSet);
+    newImplicitTupleSet.addTupleSet(tertiaryTupleNode);
+
+    // System.out.println("$$$GGGcondTupleNode=" + tertiaryTupleNode.getGlobalLocTupleSet());
+    // System.out.println("-tertiaryTupleNode=" + tertiaryTupleNode);
+    // System.out.println("-implicitFlowTupleSet=" + implicitFlowTupleSet);
+    // System.out.println("-newImplicitTupleSet=" + newImplicitTupleSet);
+
+    if (needToGenerateInterLoc(newImplicitTupleSet)) {
+      // need to create an intermediate node for the GLB of conditional locations & implicit flows
+      NTuple<Descriptor> interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      for (Iterator<NTuple<Descriptor>> idxIter = newImplicitTupleSet.iterator(); idxIter.hasNext();) {
+        NTuple<Descriptor> tuple = idxIter.next();
+        addFlowGraphEdge(md, tuple, interTuple);
+      }
+      newImplicitTupleSet.clear();
+      newImplicitTupleSet.addTuple(interTuple);
+    }
+
+    newImplicitTupleSet.addGlobalFlowTupleSet(tertiaryTupleNode.getGlobalLocTupleSet());
+
+    // System.out.println("---------newImplicitTupleSet=" + newImplicitTupleSet);
+
     // add edges from tertiaryTupleNode to all nodes of conditional nodes
-    tertiaryTupleNode.addTupleSet(implicitFlowTupleSet);
+    // tertiaryTupleNode.addTupleSet(implicitFlowTupleSet);
     analyzeFlowExpressionNode(md, nametable, tn.getTrueExpr(), tertiaryTupleNode, null,
-        implicitFlowTupleSet, false);
+        newImplicitTupleSet, false);
 
     analyzeFlowExpressionNode(md, nametable, tn.getFalseExpr(), tertiaryTupleNode, null,
-        implicitFlowTupleSet, false);
+        newImplicitTupleSet, false);
+
+    nodeSet.addGlobalFlowTupleSet(tertiaryTupleNode.getGlobalLocTupleSet());
+    nodeSet.addTupleSet(tertiaryTupleNode);
+
+    // System.out.println("#tertiary node set=" + nodeSet);
+  }
+
+  private void addMapCallerMethodDescToMethodInvokeNodeSet(MethodDescriptor caller,
+      MethodInvokeNode min) {
+    Set<MethodInvokeNode> set = mapMethodDescriptorToMethodInvokeNodeSet.get(caller);
+    if (set == null) {
+      set = new HashSet<MethodInvokeNode>();
+      mapMethodDescriptorToMethodInvokeNodeSet.put(caller, set);
+    }
+    set.add(min);
+  }
+
+  private void addParamNodeFlowingToReturnValue(MethodDescriptor md, FlowNode fn) {
+
+    if (!mapMethodDescToParamNodeFlowsToReturnValue.containsKey(md)) {
+      mapMethodDescToParamNodeFlowsToReturnValue.put(md, new HashSet<FlowNode>());
+    }
+    mapMethodDescToParamNodeFlowsToReturnValue.get(md).add(fn);
+  }
+
+  private Set<FlowNode> getParamNodeFlowingToReturnValue(MethodDescriptor md) {
 
-    nodeSet.addTupleSet(tertiaryTupleNode);
+    if (!mapMethodDescToParamNodeFlowsToReturnValue.containsKey(md)) {
+      mapMethodDescToParamNodeFlowsToReturnValue.put(md, new HashSet<FlowNode>());
+    }
 
+    return mapMethodDescToParamNodeFlowsToReturnValue.get(md);
   }
 
-  private void addMapCallerMethodDescToMethodInvokeNodeSet(MethodDescriptor caller,
-      MethodInvokeNode min) {
-    Set<MethodInvokeNode> set = mapMethodDescriptorToMethodInvokeNodeSet.get(caller);
-    if (set == null) {
-      set = new HashSet<MethodInvokeNode>();
-      mapMethodDescriptorToMethodInvokeNodeSet.put(caller, set);
+  private Set<NTuple<Location>> getPCLocTupleSet(MethodInvokeNode min) {
+    if (!mapMethodInvokeNodeToPCLocTupleSet.containsKey(min)) {
+      mapMethodInvokeNodeToPCLocTupleSet.put(min, new HashSet<NTuple<Location>>());
     }
-    set.add(min);
+    return mapMethodInvokeNodeToPCLocTupleSet.get(min);
   }
 
-  private void analyzeFlowMethodInvokeNode(MethodDescriptor md, SymbolTable nametable,
-      MethodInvokeNode min, NodeTupleSet implicitFlowTupleSet) {
+  private void analyzeFlowMethodInvokeNode(MethodDescriptor mdCaller, SymbolTable nametable,
+      MethodInvokeNode min, NodeTupleSet nodeSet, NodeTupleSet implicitFlowTupleSet) {
+
+    // System.out.println("analyzeFlowMethodInvokeNode=" + min.printNode(0));
+
+    if (!toanalyze_methodDescList.contains(min.getMethod())) {
+      return;
+    }
+
+    addMapMethodDescToMethodInvokeNodeSet(min);
+
+    Set<NTuple<Location>> pcLocTupleSet = getPCLocTupleSet(min);
+    for (Iterator iterator = implicitFlowTupleSet.iterator(); iterator.hasNext();) {
+      NTuple<Descriptor> pcDescTuple = (NTuple<Descriptor>) iterator.next();
+      if (!pcDescTuple.get(0).equals(LITERALDESC)) {
+        // here we don't need to add the literal value as a PC location
+        pcLocTupleSet.add(translateToLocTuple(mdCaller, pcDescTuple));
+      }
+    }
+
+    mapMethodInvokeNodeToArgIdxMap.put(min, new HashMap<Integer, NTuple<Descriptor>>());
 
-    addMapCallerMethodDescToMethodInvokeNodeSet(md, min);
+    if (nodeSet == null) {
+      nodeSet = new NodeTupleSet();
+    }
 
-    MethodDescriptor calleeMD = min.getMethod();
+    MethodDescriptor mdCallee = min.getMethod();
 
     NameDescriptor baseName = min.getBaseName();
     boolean isSystemout = false;
@@ -909,120 +5749,360 @@ public class LocationInference {
       isSystemout = baseName.getSymbol().equals("System.out");
     }
 
-    if (!ssjava.isSSJavaUtil(calleeMD.getClassDesc()) && !ssjava.isTrustMethod(calleeMD)
-        && !calleeMD.getModifiers().isNative() && !isSystemout) {
+    if (!ssjava.isSSJavaUtil(mdCallee.getClassDesc()) && !ssjava.isTrustMethod(mdCallee)
+        && !isSystemout) {
+
+      addMapCallerMethodDescToMethodInvokeNodeSet(mdCaller, min);
+
+      FlowGraph calleeFlowGraph = getFlowGraph(mdCallee);
+      // System.out.println("mdCallee=" + mdCallee + " calleeFlowGraph=" + calleeFlowGraph);
+      Set<FlowNode> calleeReturnSet = calleeFlowGraph.getReturnNodeSet();
+
+      // System.out.println("---calleeReturnSet=" + calleeReturnSet);
+
+      NodeTupleSet tupleSet = new NodeTupleSet();
 
-      // CompositeLocation baseLocation = null;
       if (min.getExpression() != null) {
 
         NodeTupleSet baseNodeSet = new NodeTupleSet();
-        analyzeFlowExpressionNode(calleeMD, nametable, min.getExpression(), baseNodeSet, null,
+        analyzeFlowExpressionNode(mdCaller, nametable, min.getExpression(), baseNodeSet, null,
             implicitFlowTupleSet, false);
+        // System.out.println("baseNodeSet=" + baseNodeSet);
 
-      } else {
+        assert (baseNodeSet.size() == 1);
+        NTuple<Descriptor> baseTuple = baseNodeSet.iterator().next();
+        if (baseTuple.get(0) instanceof InterDescriptor) {
+          if (baseTuple.size() > 1) {
+            throw new Error();
+          }
+          FlowNode interNode = getFlowGraph(mdCaller).getFlowNode(baseTuple);
+          baseTuple = translateBaseTuple(interNode, baseTuple);
+        }
+        mapMethodInvokeNodeToBaseTuple.put(min, baseTuple);
+
+        if (!min.getMethod().isStatic()) {
+          addArgIdxMap(min, 0, baseTuple);
+
+          for (Iterator iterator = calleeReturnSet.iterator(); iterator.hasNext();) {
+            FlowNode returnNode = (FlowNode) iterator.next();
+            NTuple<Descriptor> returnDescTuple = returnNode.getDescTuple();
+            if (returnDescTuple.startsWith(mdCallee.getThis())) {
+              // the location type of the return value is started with 'this'
+              // reference
+              NTuple<Descriptor> inFlowTuple = new NTuple<Descriptor>(baseTuple.getList());
+
+              if (inFlowTuple.get(0) instanceof InterDescriptor) {
+                // min.getExpression()
+              } else {
+
+              }
+
+              inFlowTuple.addAll(returnDescTuple.subList(1, returnDescTuple.size()));
+              // nodeSet.addTuple(inFlowTuple);
+              // System.out.println("1CREATE A NEW TUPLE=" + inFlowTuple + "  from="
+              // + mdCallee.getThis());
+              // tupleSet.addTuple(inFlowTuple);
+              tupleSet.addTuple(baseTuple);
+            } else {
+              // TODO
+              // System.out.println("returnNode=" + returnNode);
+              Set<FlowNode> inFlowSet = calleeFlowGraph.getIncomingFlowNodeSet(returnNode);
+              // System.out.println("inFlowSet=" + inFlowSet + "   from retrunNode=" + returnNode);
+              for (Iterator iterator2 = inFlowSet.iterator(); iterator2.hasNext();) {
+                FlowNode inFlowNode = (FlowNode) iterator2.next();
+                if (inFlowNode.getDescTuple().startsWith(mdCallee.getThis())) {
+                  // nodeSet.addTupleSet(baseNodeSet);
+                  // System.out.println("2CREATE A NEW TUPLE=" + baseNodeSet + "  from="
+                  // + mdCallee.getThis());
+                  tupleSet.addTupleSet(baseNodeSet);
+                }
+              }
+            }
+          }
+        }
+
+      }
+      // analyze parameter flows
+
+      if (min.numArgs() > 0) {
+
+        int offset;
         if (min.getMethod().isStatic()) {
-          // String globalLocId = ssjava.getMethodLattice(md).getGlobalLoc();
-          // if (globalLocId == null) {
-          // throw new
-          // Error("Method lattice does not define global variable location at "
-          // + generateErrorMessage(md.getClassDesc(), min));
+          offset = 0;
+        } else {
+          offset = 1;
+        }
+
+        for (int i = 0; i < min.numArgs(); i++) {
+          ExpressionNode en = min.getArg(i);
+          int idx = i + offset;
+          NodeTupleSet argTupleSet = new NodeTupleSet();
+          analyzeFlowExpressionNode(mdCaller, nametable, en, argTupleSet, false);
+          // if argument is liternal node, argTuple is set to NULL
+          // System.out.println("---arg idx=" + idx + "   argTupleSet=" + argTupleSet);
+          NTuple<Descriptor> argTuple = generateArgTuple(mdCaller, argTupleSet);
+
+          // if an argument is literal value,
+          // we need to create an itermediate node so that we could assign a composite location to
+          // that node if needed
+          if (argTuple.size() > 0
+              && (argTuple.get(0).equals(GLOBALDESC) || argTuple.get(0).equals(LITERALDESC))) {
+            /*
+             * System.out.println("***GLOBAL ARG TUPLE CASE=" + argTuple); System.out.println("8");
+             * 
+             * NTuple<Descriptor> interTuple =
+             * getFlowGraph(mdCaller).createIntermediateNode().getDescTuple(); ((InterDescriptor)
+             * interTuple.get(0)).setMethodArgIdxPair(min, idx); addFlowGraphEdge(mdCaller,
+             * argTuple, interTuple); argTuple = interTuple; addArgIdxMap(min, idx, argTuple);
+             * System.out.println("new min mapping i=" + idx + "  ->" + argTuple);
+             */
+            argTuple = new NTuple<Descriptor>();
+          }
+
+          addArgIdxMap(min, idx, argTuple);
+
+          FlowNode paramNode = calleeFlowGraph.getParamFlowNode(idx);
+
+          // check whether a param node in the callee graph has incoming flows
+          // if it has incoming flows, the corresponding arg should be lower than the current PC
+          // Descriptor prefix = paramNode.getDescTuple().get(0);
+          // if (calleeFlowGraph.getIncomingNodeSetByPrefix(prefix).size() > 0) {
+          // for (Iterator<NTuple<Descriptor>> iterator = implicitFlowTupleSet.iterator(); iterator
+          // .hasNext();) {
+          // NTuple<Descriptor> pcTuple = iterator.next();
+          // System.out.println("add edge pcTuple =" + pcTuple + " -> " + argTuple);
+          // addFlowGraphEdge(md, pcTuple, argTuple);
           // }
-          // baseLocation = new CompositeLocation(new Location(md,
-          // globalLocId));
+          // }
+
+          // System.out.println("paramNode=" + paramNode + "  calleeReturnSet=" + calleeReturnSet);
+          if (hasInFlowTo(calleeFlowGraph, paramNode, calleeReturnSet)
+              || mdCallee.getModifiers().isNative()) {
+            addParamNodeFlowingToReturnValue(mdCallee, paramNode);
+            // nodeSet.addTupleSet(argTupleSet);
+            // System.out.println("3CREATE A NEW TUPLE=" + argTupleSet + "  from=" + paramNode);
+            tupleSet.addTupleSet(argTupleSet);
+          }
+        }
+
+      }
+
+      if (mdCallee.getReturnType() != null && !mdCallee.getReturnType().isVoid()) {
+        FlowReturnNode returnHolderNode = getFlowGraph(mdCaller).createReturnNode(min);
+
+        if (needToGenerateInterLoc(tupleSet)) {
+          FlowGraph fg = getFlowGraph(mdCaller);
+          FlowNode interNode = fg.createIntermediateNode();
+          interNode.setFormHolder(true);
+
+          NTuple<Descriptor> interTuple = interNode.getDescTuple();
+
+          for (Iterator iterator = tupleSet.iterator(); iterator.hasNext();) {
+            NTuple<Descriptor> tuple = (NTuple<Descriptor>) iterator.next();
+
+            Set<NTuple<Descriptor>> addSet = new HashSet<NTuple<Descriptor>>();
+            FlowNode node = fg.getFlowNode(tuple);
+            if (node instanceof FlowReturnNode) {
+              addSet.addAll(fg.getReturnTupleSet(((FlowReturnNode) node).getReturnTupleSet()));
+            } else {
+              addSet.add(tuple);
+            }
+            for (Iterator iterator2 = addSet.iterator(); iterator2.hasNext();) {
+              NTuple<Descriptor> higher = (NTuple<Descriptor>) iterator2.next();
+              addFlowGraphEdge(mdCaller, higher, interTuple);
+            }
+          }
+
+          returnHolderNode.addTuple(interTuple);
+
+          nodeSet.addTuple(interTuple);
+          // System.out.println("ADD TUPLESET=" + interTuple + " to returnnode=" +
+          // returnHolderNode);
+
         } else {
-          // 'this' var case
-          // String thisLocId = ssjava.getMethodLattice(md).getThisLoc();
-          // baseLocation = new CompositeLocation(new Location(md, thisLocId));
-        }
-      }
-
-      // constraint case:
-      // if (constraint != null) {
-      // int compareResult =
-      // CompositeLattice.compare(constraint, baseLocation, true,
-      // generateErrorMessage(cd, min));
-      // if (compareResult != ComparisonResult.GREATER) {
-      // // if the current constraint is higher than method's THIS location
-      // // no need to check constraints!
-      // CompositeLocation calleeConstraint =
-      // translateCallerLocToCalleeLoc(calleeMD, baseLocation, constraint);
-      // // System.out.println("check method body for constraint:" + calleeMD +
-      // // " calleeConstraint="
-      // // + calleeConstraint);
-      // checkMethodBody(calleeMD.getClassDesc(), calleeMD, calleeConstraint);
-      // }
-      // }
+          returnHolderNode.addTupleSet(tupleSet);
+          // System.out.println("ADD TUPLESET=" + tupleSet + " to returnnode=" + returnHolderNode);
+        }
+        // setNode.addTupleSet(tupleSet);
+        // NodeTupleSet setFromReturnNode=new NodeTupleSet();
+        // setFromReturnNode.addTuple(tuple);
 
-      analyzeFlowMethodParameters(md, nametable, min);
+        NodeTupleSet holderTupleSet =
+            getNodeTupleSetFromReturnNode(getFlowGraph(mdCaller), returnHolderNode);
 
-      // checkCalleeConstraints(md, nametable, min, baseLocation, constraint);
+        // System.out.println("HOLDER TUPLE SET=" + holderTupleSet);
+        nodeSet.addTupleSet(holderTupleSet);
 
-      // checkCallerArgumentLocationConstraints(md, nametable, min,
-      // baseLocation, constraint);
+        nodeSet.addTuple(returnHolderNode.getDescTuple());
+      }
 
-      if (!min.getMethod().getReturnType().isVoid()) {
-        // If method has a return value, compute the highest possible return
-        // location in the caller's perspective
-        // CompositeLocation ceilingLoc =
-        // computeCeilingLocationForCaller(md, nametable, min, baseLocation,
-        // constraint);
-        // return ceilingLoc;
+      // propagateFlowsFromCallee(min, md, min.getMethod());
+
+      // when generating the global flow graph,
+      // we need to add ordering relations from the set of callee return loc tuple to LHS of the
+      // caller assignment
+      for (Iterator iterator = calleeReturnSet.iterator(); iterator.hasNext();) {
+        FlowNode calleeReturnNode = (FlowNode) iterator.next();
+        NTuple<Location> calleeReturnLocTuple =
+            translateToLocTuple(mdCallee, calleeReturnNode.getDescTuple());
+        // System.out.println("calleeReturnLocTuple=" + calleeReturnLocTuple);
+        NTuple<Location> transaltedToCaller =
+            translateToCallerLocTuple(min, mdCallee, mdCaller, calleeReturnLocTuple);
+        // System.out.println("translateToCallerLocTuple="
+        // + translateToCallerLocTuple(min, mdCallee, mdCaller, calleeReturnLocTuple));
+        if (transaltedToCaller.size() > 0) {
+          nodeSet.addGlobalFlowTuple(translateToCallerLocTuple(min, mdCallee, mdCaller,
+              calleeReturnLocTuple));
+        }
       }
-    }
 
-    // return new CompositeLocation(Location.createTopLocation(md));
+      // System.out.println("min nodeSet=" + nodeSet);
+
+    }
 
   }
 
-  private NTuple<Descriptor> getArgTupleByArgIdx(MethodInvokeNode min, int idx) {
-    return mapMethodInvokeNodeToArgIdxMap.get(min).get(new Integer(idx));
+  private NodeTupleSet getNodeTupleSetFromReturnNode(FlowGraph fg, FlowReturnNode node) {
+    NodeTupleSet nts = new NodeTupleSet();
+
+    Set<NTuple<Descriptor>> returnSet = node.getReturnTupleSet();
+
+    for (Iterator iterator = returnSet.iterator(); iterator.hasNext();) {
+      NTuple<Descriptor> tuple = (NTuple<Descriptor>) iterator.next();
+      FlowNode flowNode = fg.getFlowNode(tuple);
+      if (flowNode instanceof FlowReturnNode) {
+        returnSet.addAll(recurGetNode(fg, (FlowReturnNode) flowNode));
+      } else {
+        returnSet.add(tuple);
+      }
+    }
+
+    for (Iterator iterator = returnSet.iterator(); iterator.hasNext();) {
+      NTuple<Descriptor> nTuple = (NTuple<Descriptor>) iterator.next();
+      nts.addTuple(nTuple);
+    }
+
+    return nts;
+
   }
 
-  private void addArgIdxMap(MethodInvokeNode min, int idx, NTuple<Descriptor> argTuple) {
-    Map<Integer, NTuple<Descriptor>> mapIdxToArgTuple = mapMethodInvokeNodeToArgIdxMap.get(min);
-    if (mapIdxToArgTuple == null) {
-      mapIdxToArgTuple = new HashMap<Integer, NTuple<Descriptor>>();
-      mapMethodInvokeNodeToArgIdxMap.put(min, mapIdxToArgTuple);
+  private Set<NTuple<Descriptor>> recurGetNode(FlowGraph fg, FlowReturnNode rnode) {
+
+    Set<NTuple<Descriptor>> tupleSet = new HashSet<NTuple<Descriptor>>();
+
+    Set<NTuple<Descriptor>> returnSet = rnode.getReturnTupleSet();
+    for (Iterator iterator = returnSet.iterator(); iterator.hasNext();) {
+      NTuple<Descriptor> tuple = (NTuple<Descriptor>) iterator.next();
+      FlowNode flowNode = fg.getFlowNode(tuple);
+      if (flowNode instanceof FlowReturnNode) {
+        tupleSet.addAll(recurGetNode(fg, (FlowReturnNode) flowNode));
+      }
+      tupleSet.add(tuple);
     }
-    mapIdxToArgTuple.put(new Integer(idx), argTuple);
+
+    return tupleSet;
   }
 
-  private void analyzeFlowMethodParameters(MethodDescriptor callermd, SymbolTable nametable,
-      MethodInvokeNode min) {
+  private NTuple<Descriptor> generateArgTuple(MethodDescriptor mdCaller, NodeTupleSet argTupleSet) {
+
+    int size = 0;
+
+    // if argTupleSet is empty, it comes from the top location
+    if (argTupleSet.size() == 0) {
+      NTuple<Descriptor> descTuple = new NTuple<Descriptor>();
+      descTuple.add(LITERALDESC);
+      return descTuple;
+    }
 
-    if (min.numArgs() > 0) {
+    Set<NTuple<Descriptor>> argTupleSetNonLiteral = new HashSet<NTuple<Descriptor>>();
 
-      int offset = min.getMethod().isStatic() ? 0 : 1;
+    for (Iterator<NTuple<Descriptor>> iter = argTupleSet.iterator(); iter.hasNext();) {
+      NTuple<Descriptor> descTuple = iter.next();
+      if (!descTuple.get(0).equals(LITERALDESC)) {
+        argTupleSetNonLiteral.add(descTuple);
+      }
+    }
 
-      for (int i = 0; i < min.numArgs(); i++) {
-        ExpressionNode en = min.getArg(i);
-        NTuple<Descriptor> argTuple =
-            analyzeFlowExpressionNode(callermd, nametable, en, new NodeTupleSet(), false);
+    if (argTupleSetNonLiteral.size() > 1) {
 
-        addArgIdxMap(min, i + offset, argTuple);
+      NTuple<Descriptor> interTuple =
+          getFlowGraph(mdCaller).createIntermediateNode().getDescTuple();
+      for (Iterator<NTuple<Descriptor>> idxIter = argTupleSet.iterator(); idxIter.hasNext();) {
+        NTuple<Descriptor> tuple = idxIter.next();
+        addFlowGraphEdge(mdCaller, tuple, interTuple);
       }
+      return interTuple;
+    } else if (argTupleSetNonLiteral.size() == 1) {
+      return argTupleSetNonLiteral.iterator().next();
+    } else {
+      return argTupleSet.iterator().next();
+    }
 
+  }
+
+  private boolean hasInFlowTo(FlowGraph fg, FlowNode inNode, Set<FlowNode> nodeSet) {
+    // return true if inNode has in-flows to nodeSet
+
+    if (nodeSet.contains(inNode)) {
+      // in this case, the method directly returns a parameter variable.
+      return true;
+    }
+    // Set<FlowNode> reachableSet = fg.getReachFlowNodeSetFrom(inNode);
+    Set<FlowNode> reachableSet = fg.getReachableSetFrom(inNode.getDescTuple());
+    // System.out.println("inNode=" + inNode + "  reachalbeSet=" + reachableSet);
+
+    for (Iterator iterator = reachableSet.iterator(); iterator.hasNext();) {
+      FlowNode fn = (FlowNode) iterator.next();
+      if (nodeSet.contains(fn)) {
+        return true;
+      }
     }
+    return false;
+  }
 
+  private NTuple<Descriptor> getNodeTupleByArgIdx(MethodInvokeNode min, int idx) {
+    return mapMethodInvokeNodeToArgIdxMap.get(min).get(new Integer(idx));
   }
 
-  private void analyzeLiteralNode(MethodDescriptor md, SymbolTable nametable, LiteralNode en) {
-    // TODO Auto-generated method stub
+  private void addArgIdxMap(MethodInvokeNode min, int idx, NTuple<Descriptor> argTuple /*
+                                                                                        * NodeTupleSet
+                                                                                        * tupleSet
+                                                                                        */) {
+    Map<Integer, NTuple<Descriptor>> mapIdxToTuple = mapMethodInvokeNodeToArgIdxMap.get(min);
+    if (mapIdxToTuple == null) {
+      mapIdxToTuple = new HashMap<Integer, NTuple<Descriptor>>();
+      mapMethodInvokeNodeToArgIdxMap.put(min, mapIdxToTuple);
+    }
+    mapIdxToTuple.put(new Integer(idx), argTuple);
+  }
 
+  private void analyzeFlowLiteralNode(MethodDescriptor md, SymbolTable nametable, LiteralNode en,
+      NodeTupleSet nodeSet) {
+    NTuple<Descriptor> tuple = new NTuple<Descriptor>();
+    tuple.add(LITERALDESC);
+    nodeSet.addTuple(tuple);
   }
 
   private void analyzeFlowArrayAccessNode(MethodDescriptor md, SymbolTable nametable,
       ArrayAccessNode aan, NodeTupleSet nodeSet, boolean isLHS) {
 
+    // System.out.println("analyzeFlowArrayAccessNode aan=" + aan.printNode(0));
+    String currentArrayAccessNodeExpStr = aan.printNode(0);
+    arrayAccessNodeStack.push(aan.printNode(0));
+
     NodeTupleSet expNodeTupleSet = new NodeTupleSet();
-    analyzeFlowExpressionNode(md, nametable, aan.getExpression(), expNodeTupleSet, isLHS);
+    NTuple<Descriptor> base =
+        analyzeFlowExpressionNode(md, nametable, aan.getExpression(), expNodeTupleSet, isLHS);
+    // System.out.println("-base=" + base);
 
+    nodeSet.setMethodInvokeBaseDescTuple(base);
     NodeTupleSet idxNodeTupleSet = new NodeTupleSet();
     analyzeFlowExpressionNode(md, nametable, aan.getIndex(), idxNodeTupleSet, isLHS);
 
+    arrayAccessNodeStack.pop();
+
     if (isLHS) {
       // need to create an edge from idx to array
-
       for (Iterator<NTuple<Descriptor>> idxIter = idxNodeTupleSet.iterator(); idxIter.hasNext();) {
         NTuple<Descriptor> idxTuple = idxIter.next();
         for (Iterator<NTuple<Descriptor>> arrIter = expNodeTupleSet.iterator(); arrIter.hasNext();) {
@@ -1031,17 +6111,69 @@ public class LocationInference {
         }
       }
 
+      GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+      for (Iterator<NTuple<Location>> iterator = idxNodeTupleSet.globalIterator(); iterator
+          .hasNext();) {
+        NTuple<Location> calleeReturnLocTuple = iterator.next();
+        for (Iterator<NTuple<Descriptor>> arrIter = expNodeTupleSet.iterator(); arrIter.hasNext();) {
+          NTuple<Descriptor> arrTuple = arrIter.next();
+
+          globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple, translateToLocTuple(md, arrTuple));
+        }
+      }
+
       nodeSet.addTupleSet(expNodeTupleSet);
     } else {
-      nodeSet.addTupleSet(expNodeTupleSet);
-      nodeSet.addTupleSet(idxNodeTupleSet);
+
+      NodeTupleSet nodeSetArrayAccessExp = new NodeTupleSet();
+
+      nodeSetArrayAccessExp.addTupleSet(expNodeTupleSet);
+      nodeSetArrayAccessExp.addTupleSet(idxNodeTupleSet);
+
+      if (arrayAccessNodeStack.isEmpty()
+          || !arrayAccessNodeStack.peek().startsWith(currentArrayAccessNodeExpStr)) {
+
+        if (needToGenerateInterLoc(nodeSetArrayAccessExp)) {
+          FlowNode interNode = getFlowGraph(md).createIntermediateNode();
+          NTuple<Descriptor> interTuple = interNode.getDescTuple();
+
+          for (Iterator<NTuple<Descriptor>> iter = nodeSetArrayAccessExp.iterator(); iter.hasNext();) {
+            NTuple<Descriptor> higherTuple = iter.next();
+            addFlowGraphEdge(md, higherTuple, interTuple);
+          }
+          nodeSetArrayAccessExp.clear();
+          nodeSetArrayAccessExp.addTuple(interTuple);
+          FlowGraph fg = getFlowGraph(md);
+
+          // System.out.println("base=" + base);
+          if (base != null) {
+            fg.addMapInterLocNodeToEnclosingDescriptor(interTuple.get(0),
+                getClassTypeDescriptor(base.get(base.size() - 1)));
+            interNode.setBaseTuple(base);
+          }
+        }
+      }
+
+      nodeSet.addGlobalFlowTupleSet(idxNodeTupleSet.getGlobalLocTupleSet());
+      nodeSet.addTupleSet(nodeSetArrayAccessExp);
+
     }
 
   }
 
   private void analyzeCreateObjectNode(MethodDescriptor md, SymbolTable nametable,
-      CreateObjectNode en) {
-    // TODO Auto-generated method stub
+      CreateObjectNode en, NodeTupleSet nodeSet, NodeTupleSet implicitFlowTupleSet) {
+    // System.out.println("#analyzeCreateObjectNode=" + en.printNode(0));
+    int numArgs = en.numArgs();
+    NodeTupleSet argSet = new NodeTupleSet();
+
+    for (int i = 0; i < numArgs; i++) {
+      analyzeFlowExpressionNode(md, nametable, en.getArg(i), argSet, null, implicitFlowTupleSet,
+          false);
+    }
+
+    // System.out.println("###argSet=" + argSet);
+    nodeSet.addTupleSet(argSet);
 
   }
 
@@ -1051,6 +6183,8 @@ public class LocationInference {
     NodeTupleSet leftOpSet = new NodeTupleSet();
     NodeTupleSet rightOpSet = new NodeTupleSet();
 
+    // System.out.println("analyzeFlowOpNode=" + on.printNode(0));
+
     // left operand
     analyzeFlowExpressionNode(md, nametable, on.getLeft(), leftOpSet, null, implicitFlowTupleSet,
         false);
@@ -1097,11 +6231,16 @@ public class LocationInference {
       // there are two operands
       nodeSet.addTupleSet(leftOpSet);
       nodeSet.addTupleSet(rightOpSet);
+
+      nodeSet.addGlobalFlowTupleSet(leftOpSet.getGlobalLocTupleSet());
+      nodeSet.addGlobalFlowTupleSet(rightOpSet.getGlobalLocTupleSet());
+
       break;
 
     default:
       throw new Error(op.toString());
     }
+
   }
 
   private NTuple<Descriptor> analyzeFlowNameNode(MethodDescriptor md, SymbolTable nametable,
@@ -1114,8 +6253,13 @@ public class LocationInference {
     NameDescriptor nd = nn.getName();
 
     if (nd.getBase() != null) {
-      analyzeFlowExpressionNode(md, nametable, nn.getExpression(), nodeSet, base,
-          implicitFlowTupleSet, false);
+      base =
+          analyzeFlowExpressionNode(md, nametable, nn.getExpression(), nodeSet, base,
+              implicitFlowTupleSet, false);
+      if (base == null) {
+        // base node has the top location
+        return base;
+      }
     } else {
       String varname = nd.toString();
       if (varname.equals("this")) {
@@ -1134,22 +6278,13 @@ public class LocationInference {
         FieldDescriptor fd = (FieldDescriptor) d;
         if (fd.isStatic()) {
           if (fd.isFinal()) {
-            // if it is 'static final', the location has TOP since no one can
-            // change its value
-            // loc.addLocation(Location.createTopLocation(md));
-            // return loc;
+            // if it is 'static final', no need to have flow node for the TOP
+            // location
+            return null;
           } else {
-            // if 'static', the location has pre-assigned global loc
-            // MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
-            // String globalLocId = localLattice.getGlobalLoc();
-            // if (globalLocId == null) {
-            // throw new
-            // Error("Global location element is not defined in the method " +
-            // md);
-            // }
-            // Location globalLoc = new Location(md, globalLocId);
-            //
-            // loc.addLocation(globalLoc);
+            // if 'static', assign the default GLOBAL LOCATION to the first
+            // element of the tuple
+            base.add(GLOBALDESC);
           }
         } else {
           // the location of field access starts from this, followed by field
@@ -1160,6 +6295,10 @@ public class LocationInference {
         base.add(fd);
       } else if (d == null) {
         // access static field
+        base.add(GLOBALDESC);
+        base.add(nn.getField());
+        return base;
+
         // FieldDescriptor fd = nn.getField();addFlowGraphEdge
         //
         // MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
@@ -1178,7 +6317,6 @@ public class LocationInference {
 
       }
     }
-
     getFlowGraph(md).createNewFlowNode(base);
 
     return base;
@@ -1187,11 +6325,14 @@ public class LocationInference {
 
   private NTuple<Descriptor> analyzeFlowFieldAccessNode(MethodDescriptor md, SymbolTable nametable,
       FieldAccessNode fan, NodeTupleSet nodeSet, NTuple<Descriptor> base,
-      NodeTupleSet implicitFlowTupleSet) {
+      NodeTupleSet implicitFlowTupleSet, boolean isLHS) {
+    // System.out.println("analyzeFlowFieldAccessNode=" + fan.printNode(0));
 
+    String currentArrayAccessNodeExpStr = null;
     ExpressionNode left = fan.getExpression();
     TypeDescriptor ltd = left.getType();
     FieldDescriptor fd = fan.getField();
+    ArrayAccessNode aan = null;
 
     String varName = null;
     if (left.kind() == Kind.NameNode) {
@@ -1202,37 +6343,116 @@ public class LocationInference {
     if (ltd.isClassNameRef() || (varName != null && varName.equals("this"))) {
       // using a class name directly or access using this
       if (fd.isStatic() && fd.isFinal()) {
-        // loc.addLocation(Location.createTopLocation(md));
-        // return loc;
+        return null;
       }
     }
 
-    // if (left instanceof ArrayAccessNode) {
-    // ArrayAccessNode aan = (ArrayAccessNode) left;
-    // left = aan.getExpression();
-    // }
-    // fanNodeSet
+    NodeTupleSet idxNodeTupleSet = new NodeTupleSet();
+
+    boolean isArrayCase = false;
+    if (left instanceof ArrayAccessNode) {
+
+      isArrayCase = true;
+      aan = (ArrayAccessNode) left;
+
+      currentArrayAccessNodeExpStr = aan.printNode(0);
+      arrayAccessNodeStack.push(currentArrayAccessNodeExpStr);
+
+      left = aan.getExpression();
+      analyzeFlowExpressionNode(md, nametable, aan.getIndex(), idxNodeTupleSet, base,
+          implicitFlowTupleSet, isLHS);
+
+    }
     base =
-        analyzeFlowExpressionNode(md, nametable, left, nodeSet, base, implicitFlowTupleSet, false);
+        analyzeFlowExpressionNode(md, nametable, left, nodeSet, base, implicitFlowTupleSet, isLHS);
 
-    if (!left.getType().isPrimitive()) {
+    if (base == null) {
+      // in this case, field is TOP location
+      return null;
+    } else {
 
-      if (fd.getSymbol().equals("length")) {
-        // TODO
-        // array.length access, return the location of the array
-        // return loc;
+      NTuple<Descriptor> flowFieldTuple = new NTuple<Descriptor>(base.toList());
+
+      if (!left.getType().isPrimitive()) {
+        if (!fd.getSymbol().equals("length")) {
+          // array.length access, just have the location of the array
+          flowFieldTuple.add(fd);
+          nodeSet.removeTuple(base);
+        }
       }
+      getFlowGraph(md).createNewFlowNode(flowFieldTuple);
+
+      if (isLHS) {
+        for (Iterator<NTuple<Descriptor>> idxIter = idxNodeTupleSet.iterator(); idxIter.hasNext();) {
+          NTuple<Descriptor> idxTuple = idxIter.next();
+          getFlowGraph(md).addValueFlowEdge(idxTuple, flowFieldTuple);
+        }
 
-      base.add(fd);
+        GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+        for (Iterator<NTuple<Location>> iterator = idxNodeTupleSet.globalIterator(); iterator
+            .hasNext();) {
+          NTuple<Location> calleeReturnLocTuple = iterator.next();
+
+          globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple,
+              translateToLocTuple(md, flowFieldTuple));
+        }
+
+      } else {
+        nodeSet.addTupleSet(idxNodeTupleSet);
+
+        // if it is the array case and not the LHS case
+        if (isArrayCase) {
+          arrayAccessNodeStack.pop();
+
+          if (arrayAccessNodeStack.isEmpty()
+              || !arrayAccessNodeStack.peek().startsWith(currentArrayAccessNodeExpStr)) {
+            NodeTupleSet nodeSetArrayAccessExp = new NodeTupleSet();
+
+            nodeSetArrayAccessExp.addTuple(flowFieldTuple);
+            nodeSetArrayAccessExp.addTupleSet(idxNodeTupleSet);
+            nodeSetArrayAccessExp.addTupleSet(nodeSet);
+
+            if (needToGenerateInterLoc(nodeSetArrayAccessExp)) {
+              // System.out.println("nodeSetArrayAccessExp=" + nodeSetArrayAccessExp);
+              // System.out.println("idxNodeTupleSet.getGlobalLocTupleSet()="
+              // + idxNodeTupleSet.getGlobalLocTupleSet());
+
+              NTuple<Descriptor> interTuple =
+                  getFlowGraph(md).createIntermediateNode().getDescTuple();
+
+              for (Iterator<NTuple<Descriptor>> iter = nodeSetArrayAccessExp.iterator(); iter
+                  .hasNext();) {
+                NTuple<Descriptor> higherTuple = iter.next();
+                addFlowGraphEdge(md, higherTuple, interTuple);
+              }
+
+              FlowGraph fg = getFlowGraph(md);
+              fg.addMapInterLocNodeToEnclosingDescriptor(interTuple.get(0),
+                  getClassTypeDescriptor(base.get(base.size() - 1)));
+
+              nodeSet.clear();
+              flowFieldTuple = interTuple;
+            }
+            nodeSet.addGlobalFlowTupleSet(idxNodeTupleSet.getGlobalLocTupleSet());
+          }
+
+        }
+
+      }
+      return flowFieldTuple;
     }
 
-    getFlowGraph(md).createNewFlowNode(base);
-    return base;
+  }
+
+  private void debug_printTreeNode(TreeNode tn) {
+
+    System.out.println("DEBUG: " + tn.printNode(0) + "                line#=" + tn.getNumLine());
 
   }
 
   private void analyzeFlowAssignmentNode(MethodDescriptor md, SymbolTable nametable,
-      AssignmentNode an, NTuple<Descriptor> base, NodeTupleSet implicitFlowTupleSet) {
+      AssignmentNode an, NodeTupleSet nodeSet, NTuple<Descriptor> base,
+      NodeTupleSet implicitFlowTupleSet) {
 
     NodeTupleSet nodeSetRHS = new NodeTupleSet();
     NodeTupleSet nodeSetLHS = new NodeTupleSet();
@@ -1243,7 +6463,6 @@ public class LocationInference {
             .getBaseOp().getOp() != Operation.POSTDEC)) {
       postinc = false;
     }
-
     // if LHS is array access node, need to capture value flows between an array
     // and its index value
     analyzeFlowExpressionNode(md, nametable, an.getDest(), nodeSetLHS, null, implicitFlowTupleSet,
@@ -1254,12 +6473,35 @@ public class LocationInference {
       analyzeFlowExpressionNode(md, nametable, an.getSrc(), nodeSetRHS, null, implicitFlowTupleSet,
           false);
 
+      // System.out.println("-analyzeFlowAssignmentNode=" + an.printNode(0));
+      // System.out.println("-nodeSetLHS=" + nodeSetLHS);
+      // System.out.println("-nodeSetRHS=" + nodeSetRHS);
+      // System.out.println("-implicitFlowTupleSet=" + implicitFlowTupleSet);
+      // System.out.println("-");
+
+      if (an.getOperation().getOp() >= 2 && an.getOperation().getOp() <= 12) {
+        // if assignment contains OP+EQ operator, creates edges from LHS to LHS
+
+        for (Iterator<NTuple<Descriptor>> iter = nodeSetLHS.iterator(); iter.hasNext();) {
+          NTuple<Descriptor> fromTuple = iter.next();
+          for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
+            NTuple<Descriptor> toTuple = iter2.next();
+            addFlowGraphEdge(md, fromTuple, toTuple);
+          }
+        }
+      }
+
       // creates edges from RHS to LHS
+      NTuple<Descriptor> interTuple = null;
+      if (needToGenerateInterLoc(nodeSetRHS)) {
+        interTuple = getFlowGraph(md).createIntermediateNode().getDescTuple();
+      }
+
       for (Iterator<NTuple<Descriptor>> iter = nodeSetRHS.iterator(); iter.hasNext();) {
         NTuple<Descriptor> fromTuple = iter.next();
         for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
           NTuple<Descriptor> toTuple = iter2.next();
-          addFlowGraphEdge(md, fromTuple, toTuple);
+          addFlowGraphEdge(md, fromTuple, interTuple, toTuple);
         }
       }
 
@@ -1272,15 +6514,69 @@ public class LocationInference {
         }
       }
 
+      // create global flow edges if the callee gives return value flows to the caller
+      GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+      for (Iterator<NTuple<Location>> iterator = nodeSetRHS.globalIterator(); iterator.hasNext();) {
+        NTuple<Location> calleeReturnLocTuple = iterator.next();
+        for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
+          NTuple<Descriptor> callerLHSTuple = iter2.next();
+          // System.out.println("$$$ GLOBAL FLOW ADD=" + calleeReturnLocTuple + " -> "
+          // + translateToLocTuple(md, callerLHSTuple));
+
+          globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple,
+              translateToLocTuple(md, callerLHSTuple));
+        }
+      }
+
+      for (Iterator<NTuple<Location>> iterator = implicitFlowTupleSet.globalIterator(); iterator
+          .hasNext();) {
+        NTuple<Location> calleeReturnLocTuple = iterator.next();
+        for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
+          NTuple<Descriptor> callerLHSTuple = iter2.next();
+
+          globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple,
+              translateToLocTuple(md, callerLHSTuple));
+          // System.out.println("$$$ GLOBAL FLOW PCLOC ADD=" + calleeReturnLocTuple + " -> "
+          // + translateToLocTuple(md, callerLHSTuple));
+        }
+      }
+
     } else {
       // postinc case
+
       for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
         NTuple<Descriptor> tuple = iter2.next();
         addFlowGraphEdge(md, tuple, tuple);
       }
 
+      // creates edges from implicitFlowTupleSet to LHS
+      for (Iterator<NTuple<Descriptor>> iter = implicitFlowTupleSet.iterator(); iter.hasNext();) {
+        NTuple<Descriptor> fromTuple = iter.next();
+        for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
+          NTuple<Descriptor> toTuple = iter2.next();
+          addFlowGraphEdge(md, fromTuple, toTuple);
+        }
+      }
+
+      GlobalFlowGraph globalFlowGraph = getSubGlobalFlowGraph(md);
+      for (Iterator<NTuple<Location>> iterator = implicitFlowTupleSet.globalIterator(); iterator
+          .hasNext();) {
+        NTuple<Location> calleeReturnLocTuple = iterator.next();
+        for (Iterator<NTuple<Descriptor>> iter2 = nodeSetLHS.iterator(); iter2.hasNext();) {
+          NTuple<Descriptor> callerLHSTuple = iter2.next();
+          globalFlowGraph.addValueFlowEdge(calleeReturnLocTuple,
+              translateToLocTuple(md, callerLHSTuple));
+          // System.out.println("$$$ GLOBAL FLOW PC ADD=" + calleeReturnLocTuple + " -> "
+          // + translateToLocTuple(md, callerLHSTuple));
+        }
+      }
+
     }
 
+    if (nodeSet != null) {
+      nodeSet.addTupleSet(nodeSetLHS);
+      nodeSet.addGlobalFlowTupleSet(nodeSetLHS.getGlobalLocTupleSet());
+    }
   }
 
   public FlowGraph getFlowGraph(MethodDescriptor md) {
@@ -1289,21 +6585,130 @@ public class LocationInference {
 
   private boolean addFlowGraphEdge(MethodDescriptor md, NTuple<Descriptor> from,
       NTuple<Descriptor> to) {
-    // TODO
-    // return true if it adds a new edge
     FlowGraph graph = getFlowGraph(md);
     graph.addValueFlowEdge(from, to);
     return true;
   }
 
-  public void _debug_printGraph() {
+  private void addFlowGraphEdge(MethodDescriptor md, NTuple<Descriptor> from,
+      NTuple<Descriptor> inter, NTuple<Descriptor> to) {
+
+    FlowGraph graph = getFlowGraph(md);
+
+    if (inter != null) {
+      graph.addValueFlowEdge(from, inter);
+      graph.addValueFlowEdge(inter, to);
+    } else {
+      graph.addValueFlowEdge(from, to);
+    }
+
+  }
+
+  public void writeInferredLatticeDotFile(ClassDescriptor cd, SSJavaLattice<String> locOrder,
+      String nameSuffix) {
+    // System.out.println("@cd=" + cd);
+    // System.out.println("@sharedLoc=" + locOrder.getSharedLocSet());
+    writeInferredLatticeDotFile(cd, null, locOrder, nameSuffix);
+  }
+
+  public void writeInferredLatticeDotFile(ClassDescriptor cd, MethodDescriptor md,
+      SSJavaLattice<String> locOrder, String nameSuffix) {
+
+    String fileName = "lattice_";
+    if (md != null) {
+      fileName +=
+          cd.getSymbol().replaceAll("[\\W_]", "") + "_" + md.toString().replaceAll("[\\W_]", "");
+    } else {
+      fileName += cd.getSymbol().replaceAll("[\\W_]", "");
+    }
+
+    fileName += nameSuffix;
+
+    System.out.println("***lattice=" + fileName + "    setsize=" + locOrder.getKeySet().size());
+
+    Set<Pair<String, String>> pairSet = locOrder.getOrderingPairSet();
+
+    Set<String> addedLocSet = new HashSet<String>();
+
+    if (pairSet.size() > 0) {
+      try {
+        BufferedWriter bw = new BufferedWriter(new FileWriter(fileName + ".dot"));
+
+        bw.write("digraph " + fileName + " {\n");
+
+        for (Iterator iterator = pairSet.iterator(); iterator.hasNext();) {
+          // pair is in the form of <higher, lower>
+          Pair<String, String> pair = (Pair<String, String>) iterator.next();
+
+          String highLocId = pair.getFirst();
+          String lowLocId = pair.getSecond();
+          if (!addedLocSet.contains(highLocId)) {
+            addedLocSet.add(highLocId);
+            drawNode(bw, locOrder, highLocId);
+          }
+
+          if (!addedLocSet.contains(lowLocId)) {
+            addedLocSet.add(lowLocId);
+            drawNode(bw, locOrder, lowLocId);
+          }
+
+          bw.write(highLocId + " -> " + lowLocId + ";\n");
+        }
+        bw.write("}\n");
+        bw.close();
+
+      } catch (IOException e) {
+        e.printStackTrace();
+      }
+
+    }
+
+  }
+
+  private String convertMergeSetToString(HierarchyGraph graph, Set<HNode> mergeSet) {
+    String str = "";
+    for (Iterator iterator = mergeSet.iterator(); iterator.hasNext();) {
+      HNode merged = (HNode) iterator.next();
+      if (merged.isMergeNode()) {
+        str += convertMergeSetToString(graph, graph.getMapHNodetoMergeSet().get(merged));
+      } else {
+        str += " " + merged.getName();
+      }
+    }
+    return str;
+  }
+
+  public void addNaiveLattice(Descriptor desc, SSJavaLattice<String> lattice) {
+    desc2naiveLattice.put(desc, lattice);
+  }
+
+  private void drawNode(BufferedWriter bw, SSJavaLattice<String> lattice, String locName)
+      throws IOException {
+
+    String prettyStr;
+    if (lattice.isSharedLoc(locName)) {
+      prettyStr = locName + "*";
+    } else {
+      prettyStr = locName;
+    }
+    // HNode node = graph.getHNode(locName);
+    // if (node != null && node.isMergeNode()) {
+    // Set<HNode> mergeSet = graph.getMapHNodetoMergeSet().get(node);
+    // prettyStr += ":" + convertMergeSetToString(graph, mergeSet);
+    // }
+    bw.write(locName + " [label=\"" + prettyStr + "\"]" + ";\n");
+  }
+
+  public void _debug_writeFlowGraph() {
     Set<MethodDescriptor> keySet = mapMethodDescriptorToFlowGraph.keySet();
 
     for (Iterator<MethodDescriptor> iterator = keySet.iterator(); iterator.hasNext();) {
       MethodDescriptor md = (MethodDescriptor) iterator.next();
       FlowGraph fg = mapMethodDescriptorToFlowGraph.get(md);
+      GlobalFlowGraph subGlobalFlowGraph = getSubGlobalFlowGraph(md);
       try {
         fg.writeGraph();
+        subGlobalFlowGraph.writeGraph("_SUBGLOBAL");
       } catch (IOException e) {
         e.printStackTrace();
       }
@@ -1312,3 +6717,25 @@ public class LocationInference {
   }
 
 }
+
+class CyclicFlowException extends Exception {
+
+}
+
+class InterDescriptor extends Descriptor {
+
+  Pair<MethodInvokeNode, Integer> minArgIdxPair;
+
+  public InterDescriptor(String name) {
+    super(name);
+  }
+
+  public void setMethodArgIdxPair(MethodInvokeNode min, int idx) {
+    minArgIdxPair = new Pair<MethodInvokeNode, Integer>(min, new Integer(idx));
+  }
+
+  public Pair<MethodInvokeNode, Integer> getMethodArgIdxPair() {
+    return minArgIdxPair;
+  }
+
+}