Modified the logic for updating on backtracking to ensure that the se…

src/main/java/org/urbcomp/cupid/db/algorithm/mapmatch/onlinemm/OnlineExtendedState.java

@@ -124,5 +124,6 @@ public OnlineExtendedState getParent() {
     public void setParent(OnlineExtendedState parent) {
         this.parent = parent;
     }
+
 }
 

src/main/java/org/urbcomp/cupid/db/algorithm/mapmatch/onlinemm/OnlineSequenceState.java

@@ -0,0 +1,24 @@
+package org.urbcomp.cupid.db.algorithm.mapmatch.onlinemm;
+
+import org.urbcomp.cupid.db.algorithm.mapmatch.tihmm.inner.SequenceState;
+import org.urbcomp.cupid.db.model.point.CandidatePoint;
+import org.urbcomp.cupid.db.model.point.GPSPoint;
+
+public class OnlineSequenceState extends SequenceState {
+
+    public int time;
+    /**
+     * 构造函数
+     *
+     * @param state       原始point的candidate
+     * @param observation 原始point
+     */
+    public OnlineSequenceState(CandidatePoint state, GPSPoint observation) {
+        super(state, observation);
+    }
+
+    public OnlineSequenceState(CandidatePoint state, GPSPoint observation, int time) {
+        super(state, observation);
+        this.time = time;
+    }
+}

src/main/java/org/urbcomp/cupid/db/algorithm/mapmatch/onlinemm/OnlineViterbi.java

@@ -2,7 +2,6 @@
 
 import org.urbcomp.cupid.db.algorithm.mapmatch.tihmm.inner.ExtendedState;
 import org.urbcomp.cupid.db.algorithm.mapmatch.tihmm.inner.ForwardStepResult;
-import org.urbcomp.cupid.db.algorithm.mapmatch.tihmm.inner.SequenceState;
 import org.urbcomp.cupid.db.algorithm.mapmatch.tihmm.inner.TiViterbi;
 import org.urbcomp.cupid.db.model.point.CandidatePoint;
 import org.urbcomp.cupid.db.model.point.GPSPoint;
@@ -21,7 +20,7 @@ public class OnlineViterbi extends TiViterbi {
     // Collection of Viterbi states
     private final LinkedList<OnlineExtendedState> stateList;
     // Local solutions for the current sequence
-    private final List<SequenceState> sequenceStates;
+    private final List<OnlineSequenceState> sequenceStates;
 
     // Convergence status
     public boolean isConverge;
@@ -36,7 +35,9 @@ public class OnlineViterbi extends TiViterbi {
     // Time diff between root and previous root
     public int timeDelta;
     // Starting insert position for global sequence after algorithm interruption
-    public int insertPosition;
+    public int validStartInsertIndex;
+    // Boundary size of convergence from the current time step
+    public int windowSize;
 
     /**
      * Constructs an OnlineViterbi instance with an initial insert position of zero.
@@ -49,44 +50,70 @@ public OnlineViterbi() {
         currentRoot = null;
         previousRoot = null;
         timeDelta = 0;
-        insertPosition = 0;
+        validStartInsertIndex = 0;
+        windowSize = 0;
     }
 
     /**
      * Constructs an OnlineViterbi instance with a specified insert position.
      * For recording insert position of global sequence when algorithm breaks.
      *
-     * @param insertPosition The starting insert position for the global sequence.
+     * @param validStartInsertIndex The starting insert position for the global sequence.
      */
-    public OnlineViterbi(int insertPosition) {
+    public OnlineViterbi(int validStartInsertIndex) {
         stateList = new LinkedList<>();
         sequenceStates = new ArrayList<>();
         isConverge = false;
         isBrokenBefore = false;
         currentRoot = null;
         previousRoot = null;
         timeDelta = 0;
-        this.insertPosition = insertPosition;
+        this.validStartInsertIndex = validStartInsertIndex;
+        windowSize = 0;
     }
 
     /**
      * Constructs an OnlineViterbi instance with a specified insert position and broken state indicator.
      * This constructor is used for recording the insert position of the global sequence when the algorithm breaks.
      *
-     * @param insertPosition The starting insert position for the global sequence.
-     * @param isBrokenBefore A boolean indicating whether the algorithm was broken before this instance was created.
+     * @param validStartInsertIndex The starting insert position for the global sequence.
+     * @param isBrokenBefore        A boolean indicating whether the algorithm was broken before this instance was created.
      */
-    public OnlineViterbi(int insertPosition, boolean isBrokenBefore) {
+    public OnlineViterbi(int validStartInsertIndex, boolean isBrokenBefore) {
         stateList = new LinkedList<>();
         sequenceStates = new ArrayList<>();
         isConverge = false;
         this.isBrokenBefore = isBrokenBefore;
         currentRoot = null;
         previousRoot = null;
         timeDelta = 0;
-        this.insertPosition = insertPosition;
+        this.validStartInsertIndex = validStartInsertIndex;
+        windowSize = 0;
     }
 
+    public OnlineViterbi(int validStartInsertIndex, int windowSize) {
+        stateList = new LinkedList<>();
+        sequenceStates = new ArrayList<>();
+        isConverge = false;
+        this.isBrokenBefore = false;
+        currentRoot = null;
+        previousRoot = null;
+        timeDelta = 0;
+        this.validStartInsertIndex = validStartInsertIndex;
+        this.windowSize = windowSize;
+    }
+
+    public OnlineViterbi(int validStartInsertIndex, int windowSize, boolean isBrokenBefore) {
+        stateList = new LinkedList<>();
+        sequenceStates = new ArrayList<>();
+        isConverge = false;
+        this.isBrokenBefore = isBrokenBefore;
+        currentRoot = null;
+        previousRoot = null;
+        timeDelta = 0;
+        this.validStartInsertIndex = validStartInsertIndex;
+        this.windowSize = windowSize;
+    }
 
     /**
      * Processes the next step in the Viterbi algorithm using the given observation
@@ -95,10 +122,10 @@ public OnlineViterbi(int insertPosition, boolean isBrokenBefore) {
      * @param observation                The current GPS observation.
      * @param candidates                 List of candidate points for the current step.
      * @param emissionLogProbabilities   Map of emission log probabilities for candidate points.
-     * @param transitionLogProbabilities  Map of transition log probabilities between candidate points.
+     * @param transitionLogProbabilities Map of transition log probabilities between candidate points.
      * @param time                       The current time step.
      * @throws IllegalStateException if the method is called without initializing
-     *                                with an observation or after an HMM break.
+     *                               with an observation or after an HMM break.
      */
     public void nextStep(
             GPSPoint observation,
@@ -123,7 +150,6 @@ public void nextStep(
 
         isBroken = hmmBreak(forwardStepResult.getNewMessage());
         if (isBroken) {
-            System.out.println("viterbi stops when executing [FORWARD STEP]");
             return;
         }
 
@@ -141,7 +167,7 @@ public void nextStep(
      * @param curCandidates              List of current candidate points.
      * @param message                    Map of state probabilities.
      * @param emissionLogProbabilities   Map of emission probabilities for each candidate.
-     * @param transitionLogProbabilities  Map of transition probabilities between candidates.
+     * @param transitionLogProbabilities Map of transition probabilities between candidates.
      * @param time                       The current time step.
      * @return Results after forward extension, including updated state probabilities and states.
      */
@@ -392,23 +418,28 @@ private boolean searchForNewRoot() {
      * current root state to the previous root state.
      */
     private void traceback() {
+        int currentTime = currentRoot.getTime();
+
         System.out.println("Local path found!");
-        List<SequenceState> interLocalPath = new ArrayList<>();
-        interLocalPath.add(new SequenceState(currentRoot.getState(), currentRoot.getObservation()));
+        System.out.println("Current root time: " + currentTime);
+
+        List<OnlineSequenceState> interLocalPath = new ArrayList<>();
+        interLocalPath.add(new org.urbcomp.cupid.db.algorithm.mapmatch.onlinemm.OnlineSequenceState(currentRoot.getState(), currentRoot.getObservation(), currentTime--));
 
         int depth = isConvergedBefore() ? currentRoot.getTime() - previousRoot.getTime() - 1 : currentRoot.getTime();
-        System.out.println("current root time: " + currentRoot.getTime());
         ExtendedState current = currentRoot.getBackPointer();
 
         for (int i = 0; i < depth; i++) {
-            interLocalPath.add(new SequenceState(current.getState(), current.getObservation()));
+            interLocalPath.add(new OnlineSequenceState(current.getState(), current.getObservation(), currentTime--));
             current = current.getBackPointer();
         }
 
         assert current == null || current.getState() == previousRoot.getState();
-        System.out.println("local added sequence length: " + interLocalPath.size());
+
         Collections.reverse(interLocalPath);
         sequenceStates.addAll(interLocalPath);
+
+        System.out.println("Local added sequence length: " + interLocalPath.size());
     }
 
     /**
@@ -420,18 +451,16 @@ private void traceback() {
      */
     public void tracebackLastPart(GPSPoint observation) {
         System.out.println("traceback last part");
-        List<SequenceState> interLocalPath = new ArrayList<>();
 
+        List<OnlineSequenceState> interLocalPath = new ArrayList<>();
         CandidatePoint maxValuePoint = findMaxValuePoint(message);
-
-        interLocalPath.add(new SequenceState(maxValuePoint, observation));
+        interLocalPath.add(new OnlineSequenceState(maxValuePoint, observation));
 
         if (lastExtendedStates == null) return;
         ExtendedState current = lastExtendedStates.get(maxValuePoint);
 
-
         while (current != currentRoot) {
-            interLocalPath.add(new SequenceState(current.getState(), current.getObservation()));
+            interLocalPath.add(new OnlineSequenceState(current.getState(), current.getObservation()));
             current = current.getBackPointer();
         }
 
@@ -453,7 +482,7 @@ public LinkedList<OnlineExtendedState> getStateList() {
      *
      * @return A List of SequenceState objects.
      */
-    public List<SequenceState> getSequenceStates() {
+    public List<OnlineSequenceState> getSequenceStates() {
         return sequenceStates;
     }