Adding PacketLevelSignatureExtractor.

[pingpong.git] / Code / Projects / PacketLevelSignatureExtractor / src / main / java / edu / uci / iotproject / detection / AbstractClusterMatcher.java

diff --git a/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/AbstractClusterMatcher.java b/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/AbstractClusterMatcher.java
new file mode 100644 (file)
index 0000000..45c6a55
--- /dev/null
+++ b/Code/Projects/PacketLevelSignatureExtractor/src/main/java/edu/uci/iotproject/detection/AbstractClusterMatcher.java
@@ -0,0 +1,72 @@
+package edu.uci.iotproject.detection;
+
+import org.pcap4j.core.PcapPacket;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Base class for classes that search a traffic trace for sequences of packets that "belong to" a given cluster (in
+ * other words, classes that attempt to classify traffic as pertaining to a given cluster).
+ *
+ * @author Janus Varmarken {@literal <jvarmark@uci.edu>}
+ * @author Rahmadi Trimananda {@literal <rtrimana@uci.edu>}
+ */
+abstract public class AbstractClusterMatcher {
+
+    /**
+     * The cluster that describes the sequence of packets that this {@link AbstractClusterMatcher} is trying to detect
+     * in the observed traffic.
+     */
+    protected final List<List<PcapPacket>> mCluster;
+
+    /**
+     * Observers registered for callbacks from this {@link AbstractClusterMatcher}.
+     */
+    protected final List<ClusterMatcherObserver> mObservers;
+
+    protected AbstractClusterMatcher(List<List<PcapPacket>> cluster) {
+        // ===================== PRECONDITION SECTION =====================
+        cluster = Objects.requireNonNull(cluster, "cluster cannot be null");
+        if (cluster.isEmpty() || cluster.stream().anyMatch(inner -> inner.isEmpty())) {
+            throw new IllegalArgumentException("cluster is empty (or contains an empty inner List)");
+        }
+        for (List<PcapPacket> clusterMember : cluster) {
+            if (clusterMember.size() != cluster.get(0).size()) {
+                throw new IllegalArgumentException("All sequences in cluster must contain the same number of packets");
+            }
+        }
+        // ================================================================
+        // Let the subclass prune the provided cluster
+        mCluster = pruneCluster(cluster);
+        mObservers = new ArrayList<>();
+    }
+
+    /**
+     * Register for callbacks from this cluster matcher.
+     * @param observer The target of the callbacks.
+     */
+    public final void addObserver(ClusterMatcherObserver observer) {
+        mObservers.add(observer);
+    }
+
+    /**
+     * Deregister for callbacks from this cluster matcher.
+     * @param observer The callback target that is to be deregistered.
+     */
+    public final void removeObserver(ClusterMatcherObserver observer) {
+        mObservers.remove(observer);
+    }
+
+    /**
+     * Allows subclasses to specify how to prune the input cluster provided to the constructor.
+     * @param cluster The input cluster provided to the constructor.
+     * @return The pruned cluster to use in place of the input cluster.
+     */
+    abstract protected List<List<PcapPacket>> pruneCluster(List<List<PcapPacket>> cluster);
+
+    // TODO: move Direction outside Conversation so that this is less confusing.
+//    abstract protected Conversation.Direction[] getPacketDirections(List<PcapPacket> packets);
+
+}