Implémentation du Dijkstra en cours

be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/DijkstraAlgorithm.java

@@ -1,5 +1,17 @@
 package org.insa.graphs.algorithm.shortestpath;
 
+
+import java.util.Arrays;
+
+import java.util.Collections;
+import java.util.ArrayList;
+
+import org.insa.graphs.algorithm.AbstractSolution.Status;
+import org.insa.graphs.algorithm.utils.BinaryHeap;
+import org.insa.graphs.model.Arc;
+import org.insa.graphs.model.Graph;
+import org.insa.graphs.model.Node;
+import org.insa.graphs.model.Path;
 public class DijkstraAlgorithm extends ShortestPathAlgorithm {
 
     public DijkstraAlgorithm(ShortestPathData data) {
@@ -10,7 +22,60 @@ public class DijkstraAlgorithm extends ShortestPathAlgorithm {
     protected ShortestPathSolution doRun() {
         final ShortestPathData data = getInputData();
         ShortestPathSolution solution = null;
-        // TODO:
+        Graph graph = data.getGraph();
+        final int nbNodes=graph.size();
+        BinaryHeap<Node> tas=new BinaryHeap<Node>();
+        Label []tabLabel=new Label[nbNodes];
+        //Initilisation 
+        for(Node n:graph.getNodes())
+        {
+        	tabLabel[n.getId()]=new Label(n);
+        }
+        tabLabel[data.getOrigin().getId()].setCout(0);
+        tas.insert(data.getOrigin());
+        int nbMarque=0;
+        while(nbMarque!=nbNodes)
+        {
+        	Node X=tas.findMin();
+        	tabLabel[X.getId()].setMarque(true);
+        	nbMarque++;
+        	for(Arc a: X.getSuccessors())
+        	{
+        		Node Y=a.getDestination();
+        		if(!tabLabel[Y.getId()].isMarque())
+        		{
+        			//double cout_avant=tabLabel[Y.getId()].getCout();
+        			if((tabLabel[X.getId()].getCout()+a.getLength())<tabLabel[Y.getId()].getCout())
+        			{
+        				tabLabel[Y.getId()].setCout(tabLabel[X.getId()].getCout()+a.getLength());
+        				tas.insert(Y);
+        				tabLabel[Y.getId()].setPere(a);
+        			}
+        			
+        		}
+        	}
+        	
+        }
+     // Destination has no predecessor, the solution is infeasible...
+        if (tabLabel[data.getDestination().getId()].getPere() == null) {
+            solution = new ShortestPathSolution(data, Status.INFEASIBLE);
+        }
+        else {
+        ArrayList<Arc> arcs = new ArrayList<>();
+        Arc arc = tabLabel[data.getDestination().getId()].getPere();
+        while (arc != null) {
+            arcs.add(arc);
+            arc = tabLabel[arc.getOrigin().getId()].getPere();
+        }
+
+        // Reverse the path...
+        Collections.reverse(arcs);
+
+        // Create the final solution.
+        solution = new ShortestPathSolution(data, Status.OPTIMAL, new Path(graph, arcs));
+        }
+        
+        
         return solution;
     }
 

be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/Label.java

@@ -0,0 +1,53 @@
+package org.insa.graphs.algorithm.shortestpath;
+
+import org.insa.graphs.model.Node;
+import org.insa.graphs.model.Arc;
+
+public class Label {
+	private Node sommetCourant;
+	private boolean isMarque;
+	private double cout;
+	private Arc pere;
+	
+
+	
+	public Label(Node sommetCourant)
+	{
+		this.sommetCourant=sommetCourant;
+		this.setCout(Double.POSITIVE_INFINITY);
+		this.setMarque(false);
+		this.setPere(null);
+	}
+	
+
+	public Arc getPere() {
+		return pere;
+	}
+
+	public void setPere(Arc pere) {
+		this.pere = pere;
+	}
+
+	public boolean isMarque() {
+		return isMarque;
+	}
+
+	public void setMarque(boolean isMarque) {
+		this.isMarque = isMarque;
+	}
+
+	public Node getSommetCourant() {
+		return sommetCourant;
+	}
+
+
+	public double getCout() {
+		return cout;
+	}
+
+
+	public void setCout(double cout) {
+		this.cout = cout;
+	}
+	
+}