+++ /dev/null
-package Analysis.TaskStateAnalysis;
-import IR.*;
-import Analysis.TaskStateAnalysis.*;
-import IR.Tree.*;
-import IR.Flat.*;
-import java.util.*;
-
-
-/* Edge *****************/
-
-public class Edge {
-
- private String label;
- private FlagState target;
- private FlagState source;
- protected String dotnodeparams = new String();
-
- public Edge(FlagState target, String label) {
- this.label = label;
- this.target = target;
- }
-
- public String getLabel() {
- return label;
- }
-
- public void setSource(FlagState s) {
- this.source=s;
- }
-
- public FlagState getSource() {
- return source;
- }
-
- public FlagState getTarget() {
- return target;
- }
-
- public int hashCode(){
- return target.hashCode()^label.hashCode();
- }
-
- public void setDotNodeParameters(String param) {
- if (param == null) {
- throw new NullPointerException();
- }
- if (param.length() > 0) {
- dotnodeparams = "," + param;
- } else {
- dotnodeparams = new String();
- }
- }
- public boolean equals(Object o) {
- if (o instanceof Edge) {
- Edge e=(Edge)o;
- if (e.label.compareTo(label)!=0)
- return false;
- return e.target.equals(target);
- }
- return false;
- }
-
-
-}
--- /dev/null
+package Analysis.TaskStateAnalysis;
+import IR.*;
+import Analysis.TaskStateAnalysis.*;
+import IR.Tree.*;
+import IR.Flat.*;
+import java.util.*;
+import Util.Edge;
+
+/* Edge *****************/
+
+public class FEdge extends Edge {
+
+ private String label;
+
+ public FEdge(FlagState target, String label) {
+ super(target);
+ this.label = label;
+ }
+
+ public String getLabel() {
+ return label;
+ }
+
+ public int hashCode(){
+ return target.hashCode()^label.hashCode();
+ }
+
+ public boolean equals(Object o) {
+ if (o instanceof FEdge) {
+ FEdge e=(FEdge)o;
+ return e.label.equals(label)&&
+ e.target.equals(target);
+ }
+ return false;
+ }
+
+
+}
import IR.Flat.*;
import java.util.*;
import java.io.*;
+import Util.GraphNode;
/** This class is used to hold the flag states that a class in the Bristlecone
* program can exist in, during runtime.
*/
-public class FlagState {
- /* NodeStatus enumeration pattern ***********/
-
- public static final NodeStatus UNVISITED = new NodeStatus("UNVISITED");
- public static final NodeStatus PROCESSING = new NodeStatus("PROCESSING");
- public static final NodeStatus FINISHED = new NodeStatus("FINISHED");
+public class FlagState extends GraphNode {
public static final int ONETAG=1;
public static final int NOTAGS=0;
public static final int MULTITAGS=-1;
-
-
-
- public static class NodeStatus {
- private static String name;
- private NodeStatus(String name) { this.name = name; }
- public String toString() { return name; }
- }
-
-
- int discoverytime = -1;
- int finishingtime = -1; /* used for searches */
-
- //Hashtable<TagDescriptor,Integer> tags=new Hashtable<TagDescriptor,Integer>();
- Vector edges = new Vector();
- Vector inedges = new Vector();
- NodeStatus status = UNVISITED;
- protected String dotnodeparams = new String();
- boolean merge=false;
- String nodeoption="";
private int uid;
private static int nodeid=0;
public void setMerge() {
merge=true;
}
+
/** Class constructor
* Creates a new flagstate with all flags set to false.
* @param cd ClassDescriptor
return new FlagState(newset,cd,newtags);
}
+
public int getTagCount(String tagtype){
for (Enumeration en=getTags();en.hasMoreElements();){
TagDescriptor td=(TagDescriptor)en.nextElement();
}
-
-
public FlagState[] clearTag(TagDescriptor tag){
FlagState[] retstates;
* @return returns the classdescriptor of the flagstate.
*/
- public ClassDescriptor getClassDescriptor(){
+ public ClassDescriptor getClassDescriptor(){
return cd;
- }
+ }
/** Sets the status of a specific flag in a flagstate after cloning it.
* @param fd FlagDescriptor of the flag whose status is being set.
return cd.hashCode()^flagstate.hashCode()^tags.hashCode();
}
- public static void computeclosure(Collection nodes, Collection removed) {
- Stack tovisit=new Stack();
- tovisit.addAll(nodes);
- while(!tovisit.isEmpty()) {
- FlagState gn=(FlagState)tovisit.pop();
- for(Iterator it=gn.edges();it.hasNext();) {
- Edge edge=(Edge)it.next();
- FlagState target=edge.getTarget();
- if (!nodes.contains(target)) {
- if ((removed==null)||
- (!removed.contains(target))) {
- nodes.add(target);
- tovisit.push(target);
- }
- }
- }
- }
- }
-
- public static void boundedcomputeclosure(Collection nodes, Collection removed,int depth) {
- Stack tovisit=new Stack();
- Stack newvisit=new Stack();
- tovisit.addAll(nodes);
- for(int i=0;i<depth&&!tovisit.isEmpty();i++) {
- while(!tovisit.isEmpty()) {
- FlagState gn=(FlagState)tovisit.pop();
- for(Iterator it=gn.edges();it.hasNext();) {
- Edge edge=(Edge)it.next();
- FlagState target=edge.getTarget();
- if (!nodes.contains(target)) {
- if ((removed==null)||
- (!removed.contains(target))) {
- nodes.add(target);
- newvisit.push(target);
- }
- }
- }
- }
- tovisit=newvisit;
- newvisit=new Stack();
- }
- }
-
- public void setDotNodeParameters(String param) {
- if (param == null) {
- throw new NullPointerException();
- }
- if (param.length() > 0) {
- dotnodeparams = "," + param;
- } else {
- dotnodeparams = new String();
- }
- }
-
- public void setStatus(NodeStatus status) {
- if (status == null) {
- throw new NullPointerException();
- }
- this.status = status;
- }
-
public String getLabel() {
return "N"+uid;
}
public Enumeration getTags(){
return tags.keys();
- }
-
- public NodeStatus getStatus() {
- return this.status;
- }
-
- public Iterator edges() {
- return edges.iterator();
- }
-
- public Iterator inedges() {
- return inedges.iterator();
- }
-
- public void addEdge(Edge newedge) {
- newedge.setSource(this);
- edges.addElement(newedge);
- FlagState tonode=newedge.getTarget();
- tonode.inedges.addElement(newedge);
- }
-
- void reset() {
- discoverytime = -1;
- finishingtime = -1;
- status = UNVISITED;
- }
-
- void resetscc() {
- status = UNVISITED;
- }
-
- void discover(int time) {
- discoverytime = time;
- status = PROCESSING;
- }
-
- void finish(int time) {
- assert status == PROCESSING;
- finishingtime = time;
- status = FINISHED;
- }
-
- /** Returns finishing time for dfs */
-
- public int getFinishingTime() {
- return finishingtime;
- }
-
-
- public static class DOTVisitor {
-
- java.io.PrintWriter output;
- int tokennumber;
- int color;
-
- private DOTVisitor(java.io.OutputStream output) {
- tokennumber = 0;
- color = 0;
- this.output = new java.io.PrintWriter(output, true);
- }
-
- private String getNewID(String name) {
- tokennumber = tokennumber + 1;
- return new String (name+tokennumber);
- }
-
- Collection nodes;
- Collection special;
-
- public static void visit(java.io.OutputStream output, Collection nodes) {
- visit(output,nodes,null);
- }
-
- public static void visit(java.io.OutputStream output, Collection nodes, Collection special) {
- DOTVisitor visitor = new DOTVisitor(output);
- visitor.special=special;
- visitor.nodes = nodes;
- visitor.make();
- }
-
- private void make() {
- output.println("digraph dotvisitor {");
- output.println("\trotate=90;");
- /* output.println("\tpage=\"8.5,11\";");
- output.println("\tnslimit=1000.0;");
- output.println("\tnslimit1=1000.0;");
- output.println("\tmclimit=1000.0;");
- output.println("\tremincross=true;");*/
- output.println("\tnode [fontsize=10,height=\"0.1\", width=\"0.1\"];");
- output.println("\tedge [fontsize=6];");
- traverse();
- output.println("}\n");
- }
-
- private void traverse() {
- Iterator i = nodes.iterator();
- while (i.hasNext()) {
- FlagState gn = (FlagState) i.next();
- Iterator edges = gn.edges();
- String label = gn.getTextLabel(); // + " [" + gn.discoverytime + "," + gn.finishingtime + "];";
- String option=gn.nodeoption;
- if (special!=null&&special.contains(gn))
- option+=",shape=box";
- if (!gn.merge)
- output.println("\t" + gn.getLabel() + " [label=\"" + label + "\"" + gn.dotnodeparams + option+"];");
- if (!gn.merge)
- while (edges.hasNext()) {
- Edge edge = (Edge) edges.next();
- FlagState node = edge.getTarget();
- if (nodes.contains(node)) {
- for(Iterator nodeit=nonmerge(node).iterator();nodeit.hasNext();) {
- FlagState node2=(FlagState)nodeit.next();
- String edgelabel = "label=\"" + edge.getLabel() + "\"";
- output.println("\t" + gn.getLabel() + " -> " + node2.getLabel() + " [" + edgelabel + edge.dotnodeparams + "];");
- }
- }
- }
- }
- }
-
-
- Set nonmerge(FlagState gn) {
- HashSet newset=new HashSet();
- HashSet toprocess=new HashSet();
- toprocess.add(gn);
- while(!toprocess.isEmpty()) {
- FlagState gn2=(FlagState)toprocess.iterator().next();
- toprocess.remove(gn2);
- if (!gn2.merge)
- newset.add(gn2);
- else {
- Iterator edges = gn2.edges();
- while (edges.hasNext()) {
- Edge edge = (Edge) edges.next();
- FlagState node = edge.getTarget();
- if (!newset.contains(node)&&nodes.contains(node))
- toprocess.add(node);
- }
- }
- }
- return newset;
- }
-
- }
-
- /** This function returns the set of nodes involved in cycles.
- * It only considers cycles containing nodes in the set 'nodes'.
- */
- public static Set findcycles(Collection nodes) {
- HashSet cycleset=new HashSet();
- SCC scc=DFS.computeSCC(nodes);
- if (!scc.hasCycles())
- return cycleset;
- for(int i=0;i<scc.numSCC();i++) {
- if (scc.hasCycle(i))
- cycleset.addAll(scc.getSCC(i));
- }
- return cycleset;
- }
-
- public static class SCC {
- boolean acyclic;
- HashMap map,revmap;
- int numscc;
- public SCC(boolean acyclic, HashMap map,HashMap revmap,int numscc) {
- this.acyclic=acyclic;
- this.map=map;
- this.revmap=revmap;
- this.numscc=numscc;
- }
-
- /** Returns whether the graph has any cycles */
- public boolean hasCycles() {
- return !acyclic;
- }
-
- /** Returns the number of Strongly Connected Components */
- public int numSCC() {
- return numscc;
- }
-
- /** Returns the strongly connected component number for the FlagState gn*/
- public int getComponent(FlagState gn) {
- return ((Integer)revmap.get(gn)).intValue();
- }
-
- /** Returns the set of nodes in the strongly connected component i*/
- public Set getSCC(int i) {
- Integer scc=new Integer(i);
- return (Set)map.get(scc);
- }
-
- /** Returns whether the strongly connected component i contains a cycle */
- boolean hasCycle(int i) {
- Integer scc=new Integer(i);
- Set s=(Set)map.get(scc);
- if (s.size()>1)
- return true;
- Object [] array=s.toArray();
- FlagState gn=(FlagState)array[0];
- for(Iterator it=gn.edges();it.hasNext();) {
- Edge e=(Edge)it.next();
- if (e.getTarget()==gn)
- return true; /* Self Cycle */
- }
- return false;
- }
}
-
- /**
- * DFS encapsulates the depth first search algorithm
- */
- public static class DFS {
-
- int time = 0;
- int sccindex = 0;
- Collection nodes;
- Vector finishingorder=null;
- HashMap sccmap;
- HashMap sccmaprev;
-
- private DFS(Collection nodes) {
- this.nodes = nodes;
- }
- /** Calculates the strong connected components for the graph composed
- * of the set of nodes 'nodes'*/
- public static SCC computeSCC(Collection nodes) {
- if (nodes==null) {
- throw new NullPointerException();
- }
- DFS dfs=new DFS(nodes);
- dfs.sccmap=new HashMap();
- dfs.sccmaprev=new HashMap();
- dfs.finishingorder=new Vector();
- boolean acyclic=dfs.go();
- for (Iterator it = nodes.iterator();it.hasNext();) {
- FlagState gn = (FlagState) it.next();
- gn.resetscc();
- }
- for(int i=dfs.finishingorder.size()-1;i>=0;i--) {
- FlagState gn=(FlagState)dfs.finishingorder.get(i);
- if (gn.getStatus() == UNVISITED) {
- dfs.dfsprev(gn);
- dfs.sccindex++; /* Increment scc index */
- }
- }
- return new SCC(acyclic,dfs.sccmap,dfs.sccmaprev,dfs.sccindex);
- }
-
- void dfsprev(FlagState gn) {
- if (gn.getStatus()==FINISHED||!nodes.contains(gn))
- return;
- gn.setStatus(FINISHED);
- Integer i=new Integer(sccindex);
- if (!sccmap.containsKey(i))
- sccmap.put(i,new HashSet());
- ((Set)sccmap.get(i)).add(gn);
- sccmaprev.put(gn,i);
- for(Iterator edgeit=gn.inedges();edgeit.hasNext();) {
- Edge e=(Edge)edgeit.next();
- FlagState gn2=e.getSource();
- dfsprev(gn2);
- }
- }
-
- public static boolean depthFirstSearch(Collection nodes) {
- if (nodes == null) {
- throw new NullPointerException();
- }
-
- DFS dfs = new DFS(nodes);
- return dfs.go();
- }
-
- private boolean go() {
- Iterator i;
- time = 0;
- boolean acyclic=true;
- i = nodes.iterator();
- while (i.hasNext()) {
- FlagState gn = (FlagState) i.next();
- gn.reset();
- }
-
- i = nodes.iterator();
- while (i.hasNext()) {
- FlagState gn = (FlagState) i.next();
- assert gn.getStatus() != PROCESSING;
- if (gn.getStatus() == UNVISITED) {
- if (!dfs(gn))
- acyclic=false;
- }
- }
- return acyclic;
- }
-
- private boolean dfs(FlagState gn) {
- boolean acyclic=true;
- gn.discover(time++);
- Iterator edges = gn.edges();
-
- while (edges.hasNext()) {
- Edge edge = (Edge) edges.next();
- FlagState node = edge.getTarget();
- if (!nodes.contains(node)) /* Skip nodes which aren't in the set */
- continue;
- if (node.getStatus() == UNVISITED) {
- if (!dfs(node))
- acyclic=false;
- } else if (node.getStatus()==PROCESSING) {
- acyclic=false;
- }
- }
- if (finishingorder!=null)
- finishingorder.add(gn);
- gn.finish(time++);
- return acyclic;
- }
- } /* end DFS */
}
}
//seen this node already
fs_taskexit=canonicalizeFlagState(sourcenodes,fs_taskexit);
- Edge newedge=new Edge(fs_taskexit,taskname);
+ FEdge newedge=new FEdge(fs_taskexit,taskname);
fs.addEdge(newedge);
}
}
toprocess.add(fstemp);
fstemp=canonicalizeFlagState(sourcenodes,fstemp);
- fs.addEdge(new Edge(fstemp,"Runtime"));
+ fs.addEdge(new FEdge(fstemp,"Runtime"));
}
}
}
--- /dev/null
+package Util;
+
+/* Edge *****************/
+
+public class Edge {
+ protected GraphNode target;
+ protected GraphNode source;
+ protected String dotnodeparams = new String();
+
+ public Edge(GraphNode target) {
+ this.target = target;
+ }
+
+ public String getLabel() {
+ return "";
+ }
+
+ public void setSource(GraphNode s) {
+ this.source=s;
+ }
+
+ public GraphNode getSource() {
+ return source;
+ }
+
+ public GraphNode getTarget() {
+ return target;
+ }
+
+ public void setDotNodeParameters(String param) {
+ if (param == null) {
+ throw new NullPointerException();
+ }
+ if (param.length() > 0) {
+ dotnodeparams = "," + param;
+ } else {
+ dotnodeparams = new String();
+ }
+ }
+}
--- /dev/null
+package Util;
+
+import java.util.*;
+import java.io.*;
+
+public class GraphNode {
+ /* NodeStatus enumeration pattern ***********/
+
+ public static final NodeStatus UNVISITED = new NodeStatus("UNVISITED");
+ public static final NodeStatus PROCESSING = new NodeStatus("PROCESSING");
+ public static final NodeStatus FINISHED = new NodeStatus("FINISHED");
+
+ public static class NodeStatus {
+ private static String name;
+ private NodeStatus(String name) { this.name = name; }
+ public String toString() { return name; }
+ }
+
+ int discoverytime = -1;
+ int finishingtime = -1; /* used for searches */
+
+ Vector edges = new Vector();
+ Vector inedges = new Vector();
+ NodeStatus status = UNVISITED;
+ String dotnodeparams = new String();
+ public boolean merge=false;
+ public String nodeoption="";
+
+ public void setOption(String option) {
+ this.nodeoption=","+option;
+ }
+
+ public void setMerge() {
+ merge=true;
+ }
+
+ public static void computeclosure(Collection nodes, Collection removed) {
+ Stack tovisit=new Stack();
+ tovisit.addAll(nodes);
+ while(!tovisit.isEmpty()) {
+ GraphNode gn=(GraphNode)tovisit.pop();
+ for(Iterator it=gn.edges();it.hasNext();) {
+ Edge edge=(Edge)it.next();
+ GraphNode target=edge.getTarget();
+ if (!nodes.contains(target)) {
+ if ((removed==null)||
+ (!removed.contains(target))) {
+ nodes.add(target);
+ tovisit.push(target);
+ }
+ }
+ }
+ }
+ }
+
+ public static void boundedcomputeclosure(Collection nodes, Collection removed,int depth) {
+ Stack tovisit=new Stack();
+ Stack newvisit=new Stack();
+ tovisit.addAll(nodes);
+ for(int i=0;i<depth&&!tovisit.isEmpty();i++) {
+ while(!tovisit.isEmpty()) {
+ GraphNode gn=(GraphNode)tovisit.pop();
+ for(Iterator it=gn.edges();it.hasNext();) {
+ Edge edge=(Edge)it.next();
+ GraphNode target=edge.getTarget();
+ if (!nodes.contains(target)) {
+ if ((removed==null)||
+ (!removed.contains(target))) {
+ nodes.add(target);
+ newvisit.push(target);
+ }
+ }
+ }
+ }
+ tovisit=newvisit;
+ newvisit=new Stack();
+ }
+ }
+
+ public void setDotNodeParameters(String param) {
+ if (param == null) {
+ throw new NullPointerException();
+ }
+ if (param.length() > 0) {
+ dotnodeparams = "," + param;
+ } else {
+ dotnodeparams = new String();
+ }
+ }
+
+ public void setStatus(NodeStatus status) {
+ if (status == null) {
+ throw new NullPointerException();
+ }
+ this.status = status;
+ }
+
+ public String getLabel() {
+ return "";
+ }
+
+ public String getTextLabel() {
+ return "";
+ }
+
+ public NodeStatus getStatus() {
+ return this.status;
+ }
+
+ public Iterator edges() {
+ return edges.iterator();
+ }
+
+ public Iterator inedges() {
+ return inedges.iterator();
+ }
+
+ public void addEdge(Edge newedge) {
+ newedge.setSource(this);
+ edges.addElement(newedge);
+ GraphNode tonode=newedge.getTarget();
+ tonode.inedges.addElement(newedge);
+ }
+
+ void reset() {
+ discoverytime = -1;
+ finishingtime = -1;
+ status = UNVISITED;
+ }
+
+ void resetscc() {
+ status = UNVISITED;
+ }
+
+ void discover(int time) {
+ discoverytime = time;
+ status = PROCESSING;
+ }
+
+ void finish(int time) {
+ assert status == PROCESSING;
+ finishingtime = time;
+ status = FINISHED;
+ }
+
+ /** Returns finishing time for dfs */
+
+ public int getFinishingTime() {
+ return finishingtime;
+ }
+
+
+ public static class DOTVisitor {
+
+ java.io.PrintWriter output;
+ int tokennumber;
+ int color;
+
+ private DOTVisitor(java.io.OutputStream output) {
+ tokennumber = 0;
+ color = 0;
+ this.output = new java.io.PrintWriter(output, true);
+ }
+
+ private String getNewID(String name) {
+ tokennumber = tokennumber + 1;
+ return new String (name+tokennumber);
+ }
+
+ Collection nodes;
+ Collection special;
+
+ public static void visit(java.io.OutputStream output, Collection nodes) {
+ visit(output,nodes,null);
+ }
+
+ public static void visit(java.io.OutputStream output, Collection nodes, Collection special) {
+ DOTVisitor visitor = new DOTVisitor(output);
+ visitor.special=special;
+ visitor.nodes = nodes;
+ visitor.make();
+ }
+
+ private void make() {
+ output.println("digraph dotvisitor {");
+ output.println("\trotate=90;");
+ /* output.println("\tpage=\"8.5,11\";");
+ output.println("\tnslimit=1000.0;");
+ output.println("\tnslimit1=1000.0;");
+ output.println("\tmclimit=1000.0;");
+ output.println("\tremincross=true;");*/
+ output.println("\tnode [fontsize=10,height=\"0.1\", width=\"0.1\"];");
+ output.println("\tedge [fontsize=6];");
+ traverse();
+ output.println("}\n");
+ }
+
+ private void traverse() {
+ Set cycleset=GraphNode.findcycles(nodes);
+
+ Iterator i = nodes.iterator();
+ while (i.hasNext()) {
+ GraphNode gn = (GraphNode) i.next();
+ Iterator edges = gn.edges();
+ String label = gn.getTextLabel();
+ String option=gn.nodeoption;
+ if (special!=null&&special.contains(gn))
+ option+=",shape=box";
+ if (!gn.merge)
+ output.println("\t" + gn.getLabel() + " [label=\"" + label + "\"" + gn.dotnodeparams + option+"];");
+
+ if (!gn.merge)
+ while (edges.hasNext()) {
+ Edge edge = (Edge) edges.next();
+ GraphNode node = edge.getTarget();
+ if (nodes.contains(node)) {
+ for(Iterator nodeit=nonmerge(node).iterator();nodeit.hasNext();) {
+ GraphNode node2=(GraphNode)nodeit.next();
+ String edgelabel = "label=\"" + edge.getLabel() + "\"" ;
+ output.println("\t" + gn.getLabel() + " -> " + node2.getLabel() + " [" + edgelabel + edge.dotnodeparams + "];");
+ }
+ }
+ }
+ }
+ }
+
+ Set nonmerge(GraphNode gn) {
+ HashSet newset=new HashSet();
+ HashSet toprocess=new HashSet();
+ toprocess.add(gn);
+ while(!toprocess.isEmpty()) {
+ GraphNode gn2=(GraphNode)toprocess.iterator().next();
+ toprocess.remove(gn2);
+ if (!gn2.merge)
+ newset.add(gn2);
+ else {
+ Iterator edges = gn2.edges();
+ while (edges.hasNext()) {
+ Edge edge = (Edge) edges.next();
+ GraphNode node = edge.getTarget();
+ if (!newset.contains(node)&&nodes.contains(node))
+ toprocess.add(node);
+ }
+ }
+ }
+ return newset;
+ }
+
+ }
+
+ /** This function returns the set of nodes involved in cycles.
+ * It only considers cycles containing nodes in the set 'nodes'.
+ */
+ public static Set findcycles(Collection nodes) {
+ HashSet cycleset=new HashSet();
+ SCC scc=DFS.computeSCC(nodes);
+ if (!scc.hasCycles())
+ return cycleset;
+ for(int i=0;i<scc.numSCC();i++) {
+ if (scc.hasCycle(i))
+ cycleset.addAll(scc.getSCC(i));
+ }
+ return cycleset;
+ }
+
+ public static class SCC {
+ boolean acyclic;
+ HashMap map,revmap;
+ int numscc;
+ public SCC(boolean acyclic, HashMap map,HashMap revmap,int numscc) {
+ this.acyclic=acyclic;
+ this.map=map;
+ this.revmap=revmap;
+ this.numscc=numscc;
+ }
+
+ /** Returns whether the graph has any cycles */
+ public boolean hasCycles() {
+ return !acyclic;
+ }
+
+ /** Returns the number of Strongly Connected Components */
+ public int numSCC() {
+ return numscc;
+ }
+
+ /** Returns the strongly connected component number for the GraphNode gn*/
+ public int getComponent(GraphNode gn) {
+ return ((Integer)revmap.get(gn)).intValue();
+ }
+
+ /** Returns the set of nodes in the strongly connected component i*/
+ public Set getSCC(int i) {
+ Integer scc=new Integer(i);
+ return (Set)map.get(scc);
+ }
+
+ /** Returns whether the strongly connected component i contains a cycle */
+ boolean hasCycle(int i) {
+ Integer scc=new Integer(i);
+ Set s=(Set)map.get(scc);
+ if (s.size()>1)
+ return true;
+ Object [] array=s.toArray();
+ GraphNode gn=(GraphNode)array[0];
+ for(Iterator it=gn.edges();it.hasNext();) {
+ Edge e=(Edge)it.next();
+ if (e.getTarget()==gn)
+ return true; /* Self Cycle */
+ }
+ return false;
+ }
+ }
+
+ /**
+ * DFS encapsulates the depth first search algorithm
+ */
+ public static class DFS {
+
+ int time = 0;
+ int sccindex = 0;
+ Collection nodes;
+ Vector finishingorder=null;
+ HashMap sccmap;
+ HashMap sccmaprev;
+
+ private DFS(Collection nodes) {
+ this.nodes = nodes;
+ }
+ /** Calculates the strong connected components for the graph composed
+ * of the set of nodes 'nodes'*/
+ public static SCC computeSCC(Collection nodes) {
+ if (nodes==null) {
+ throw new NullPointerException();
+ }
+ DFS dfs=new DFS(nodes);
+ dfs.sccmap=new HashMap();
+ dfs.sccmaprev=new HashMap();
+ dfs.finishingorder=new Vector();
+ boolean acyclic=dfs.go();
+ for (Iterator it = nodes.iterator();it.hasNext();) {
+ GraphNode gn = (GraphNode) it.next();
+ gn.resetscc();
+ }
+ for(int i=dfs.finishingorder.size()-1;i>=0;i--) {
+ GraphNode gn=(GraphNode)dfs.finishingorder.get(i);
+ if (gn.getStatus() == UNVISITED) {
+ dfs.dfsprev(gn);
+ dfs.sccindex++; /* Increment scc index */
+ }
+ }
+ return new SCC(acyclic,dfs.sccmap,dfs.sccmaprev,dfs.sccindex);
+ }
+
+ void dfsprev(GraphNode gn) {
+ if (gn.getStatus()==FINISHED||!nodes.contains(gn))
+ return;
+ gn.setStatus(FINISHED);
+ Integer i=new Integer(sccindex);
+ if (!sccmap.containsKey(i))
+ sccmap.put(i,new HashSet());
+ ((Set)sccmap.get(i)).add(gn);
+ sccmaprev.put(gn,i);
+ for(Iterator edgeit=gn.inedges();edgeit.hasNext();) {
+ Edge e=(Edge)edgeit.next();
+ GraphNode gn2=e.getSource();
+ dfsprev(gn2);
+ }
+ }
+
+ public static boolean depthFirstSearch(Collection nodes) {
+ if (nodes == null) {
+ throw new NullPointerException();
+ }
+
+ DFS dfs = new DFS(nodes);
+ return dfs.go();
+ }
+
+ private boolean go() {
+ Iterator i;
+ time = 0;
+ boolean acyclic=true;
+ i = nodes.iterator();
+ while (i.hasNext()) {
+ GraphNode gn = (GraphNode) i.next();
+ gn.reset();
+ }
+
+ i = nodes.iterator();
+ while (i.hasNext()) {
+ GraphNode gn = (GraphNode) i.next();
+ assert gn.getStatus() != PROCESSING;
+ if (gn.getStatus() == UNVISITED) {
+ if (!dfs(gn))
+ acyclic=false;
+ }
+ }
+ return acyclic;
+ }
+
+ private boolean dfs(GraphNode gn) {
+ boolean acyclic=true;
+ gn.discover(time++);
+ Iterator edges = gn.edges();
+
+ while (edges.hasNext()) {
+ Edge edge = (Edge) edges.next();
+ GraphNode node = edge.getTarget();
+ if (!nodes.contains(node)) /* Skip nodes which aren't in the set */
+ continue;
+ if (node.getStatus() == UNVISITED) {
+ if (!dfs(node))
+ acyclic=false;
+ } else if (node.getStatus()==PROCESSING) {
+ acyclic=false;
+ }
+ }
+ if (finishingorder!=null)
+ finishingorder.add(gn);
+ gn.finish(time++);
+ return acyclic;
+ }
+
+ } /* end DFS */
+
+}
projects / IRC.git / commitdiff