Fixed termination of parrallel processing

Comparison/src/main/java/cz/fidentis/analyst/visitors/mesh/HausdorffDistance.java

@@ -115,8 +115,6 @@ public class HausdorffDistance extends MeshVisitor  {
     
     private final boolean parallel;
     
-    protected static final ExecutorService EXECUTOR = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
-    
     /**
      * The source triangular mesh (set of mesh facets) stred in k-d tree.
      */
@@ -270,34 +268,23 @@ public class HausdorffDistance extends MeshVisitor  {
         final List<MeshPoint> vertices = comparedFacet.getVertices();
         final List<Future<KdTreeVisitor>> results = new ArrayList<>(vertices.size());
         
+        ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
+        
         for (int i = 0; i < vertices.size(); i++) { // for each vertex of comparedFacet
-            MeshPoint inspectedPoint = vertices.get(i);
-            
-            KdTreeVisitor visitor = null;
-            switch (getStrategy()) {
-                case POINT_TO_POINT_ABSOLUTE:
-                    visitor = new KdTreeDistance(inspectedPoint.getPosition(), inParallel());
-                    break;
-                case POINT_TO_POINT:
-                    visitor = new KdTreeDistanceToVertices(inspectedPoint.getPosition(), inParallel());
-                    break;
-                default:
-                case POINT_TO_TRIANGLE_APPROXIMATE:
-                    visitor =  new KdTreeApproxDistanceToTriangles(inspectedPoint.getPosition(), inParallel());
-                    break;
-            }
-            
-            kdTree.accept(visitor); // compute the distance for i-th vertex
+            KdTreeVisitor visitor = instantiateVisitor(vertices.get(i).getPosition());
+            kdTree.accept(visitor); // compute the distance for i-th vertex or prepare the visitor for computation
             
             if (inParallel()) { // fork and continue
-                final Future<KdTreeVisitor> result = EXECUTOR.submit(visitor); 
-                results.add(result);
-            } else { // get and update distance immediately
-                addDistanceToPoint(visitor, inspectedPoint, distList);
+                results.add(executor.submit(visitor));
+            } else { // process distance results immediately
+                addDistanceToPoint(visitor, vertices.get(i), distList);
             }
         }
             
-        if (inParallel()) { // process asynchronous calls
+        if (inParallel()) { // process asynchronous computation of distance
+            executor.shutdown();
+            while (!executor.isTerminated()){
+            }
             try {
                 int i = 0;
                 for (Future<KdTreeVisitor> res: results) {
@@ -311,6 +298,18 @@ public class HausdorffDistance extends MeshVisitor  {
         }
     }
     
+    protected KdTreeVisitor instantiateVisitor(Vector3d inspectedPoint) {
+        switch (getStrategy()) {
+            case POINT_TO_POINT_ABSOLUTE:
+                return new KdTreeDistance(inspectedPoint, inParallel());
+            case POINT_TO_POINT:
+                return new KdTreeDistanceToVertices(inspectedPoint, inParallel());
+            default:
+            case POINT_TO_TRIANGLE_APPROXIMATE:
+                return new KdTreeApproxDistanceToTriangles(inspectedPoint, inParallel());
+        }
+    }
+    
     protected void addDistanceToPoint(KdTreeVisitor vis, MeshPoint point, List<Double> pointDistances) {
         if (relativeDist && vis instanceof DistanceWithNearestPoints) {
             double relDist = checkDist((DistanceWithNearestPoints)vis, point);

MeshModel/src/main/java/cz/fidentis/analyst/mesh/core/MeshModel.java

@@ -89,17 +89,11 @@ public class MeshModel {
      * Otherwise, the visitor is applied sequentionally (and synchronously).
      * 
      * @param visitor Visitor to be apllied for the computation
-     * @param exec Exisitng executor. If {@code null}, then a new private executor is used.
      * @throws {@code NullPointerException} if the visitor is {@code null}
      */
-    public void compute(MeshVisitor visitor, ExecutorService exec) {
+    public void compute(MeshVisitor visitor) {
         if (visitor.isAsynchronous() && visitor.isThreadSafe()) {
-            ExecutorService executor = exec;
-            if (executor == null) {
-                int threads = Runtime.getRuntime().availableProcessors();
-                executor = Executors.newFixedThreadPool(threads);
-            }
-            
+            ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
             List<Future<MeshVisitor>> results = new LinkedList<>();
             
             for (MeshFacet f: this.facets) {
@@ -108,7 +102,9 @@ public class MeshModel {
                 results.add(result);
             }
             
-            //executor.shutdown();
+            executor.shutdown();
+            while (!executor.isTerminated()){
+            }
             
             try {
                 for (Future<MeshVisitor> f : results) { 
@@ -124,15 +120,6 @@ public class MeshModel {
         }
     }
     
-    /**
-     * Applies the visitor to all mesh facets, either sequentially or in parallel.
-     * 
-     * @param visitor Visitor to be apllied
-     */
-    public void compute(MeshVisitor visitor) {
-        compute(visitor, null);
-    }
-    
     /**
      * Registers listeners (objects concerned in the mesh model changes) to receive events.
      * If listener is {@code null}, no exception is thrown and no action is taken.