Fix broken size cacheing in Mask*Set

Author: agdphd

jgrapht-core/src/main/java/org/jgrapht/graph/MaskEdgeSet.java

@@ -59,8 +59,6 @@ class MaskEdgeSet<V, E>
 
     private transient TypeUtil<E> edgeTypeDecl = null;
 
-    private int size;
-
     public MaskEdgeSet(
         Graph<V, E> graph,
         Set<E> edgeSet,
@@ -69,7 +67,6 @@ public MaskEdgeSet(
         this.graph = graph;
         this.edgeSet = edgeSet;
         this.mask = mask;
-        this.size = -1;
     }
 
     /**
@@ -102,14 +99,7 @@ public MaskEdgeSet(
      */
     @Override public int size()
     {
-        if (this.size == -1) {
-            this.size = 0;
-            for (Iterator<E> iter = iterator(); iter.hasNext();) {
-                iter.next();
-                this.size++;
-            }
-        }
-        return this.size;
+        return (int) edgeSet.stream().filter(e -> contains(e)).count();
     }
 
     private class MaskEdgeSetNextElementFunctor

jgrapht-core/src/main/java/org/jgrapht/graph/MaskVertexSet.java

@@ -52,8 +52,6 @@ class MaskVertexSet<V, E>
 {
     private MaskFunctor<V, E> mask;
 
-    private int size;
-
     private Set<V> vertexSet;
 
     private transient TypeUtil<V> vertexTypeDecl = null;
@@ -62,17 +60,21 @@ public MaskVertexSet(Set<V> vertexSet, MaskFunctor<V, E> mask)
     {
         this.vertexSet = vertexSet;
         this.mask = mask;
-        this.size = -1;
     }
 
     /**
      * @see java.util.Collection#contains(java.lang.Object)
      */
     @Override public boolean contains(Object o)
     {
-        return
-            !this.mask.isVertexMasked(TypeUtil.uncheckedCast(o, vertexTypeDecl))
-            && this.vertexSet.contains(o);
+        // Type system shenanigans to check whether o is a vertex
+        try {
+            V v = (V) o;
+            return vertexSet.contains(v)
+                && !mask.isVertexMasked(v);
+        } catch (ClassCastException e) {
+            return false;
+        }
     }
 
     /**
@@ -88,14 +90,7 @@ public MaskVertexSet(Set<V> vertexSet, MaskFunctor<V, E> mask)
      */
     @Override public int size()
     {
-        if (this.size == -1) {
-            this.size = 0;
-            for (Iterator<V> iter = iterator(); iter.hasNext();) {
-                iter.next();
-                this.size++;
-            }
-        }
-        return this.size;
+        return (int) vertexSet.stream().filter(v -> contains(v)).count();
     }
 
     private class MaskVertexSetNextElementFunctor

jgrapht-core/src/test/java/org/jgrapht/graph/MaskEdgeSetTest.java

@@ -20,7 +20,7 @@
  * the Eclipse Foundation.
  */
 /* --------------------------
- * AsUndirectedGraphTest.java
+ * MaxEdgeSetTest.java
  * --------------------------
  * (C) Copyright 2016-, by Andrew Gainer-Dewar and Contributors.
  *
@@ -54,24 +54,11 @@ public class MaskEdgeSetTest
     private String v4 = "v4";
     private DefaultEdge e1, e2, e3, loop1, loop2;
 
-    private MaskEdgeSet<String, DefaultEdge> vertexMaskedEdgeSet;
-
-    // Functor that masks vertex v1 and no edges
-    MaskFunctor<String, DefaultEdge> vertexMaskingFunctor = new MaskFunctor<String, DefaultEdge> () {
-            @Override
-            public boolean isEdgeMasked (DefaultEdge edge) {
-                return false;
-            }
-
-            @Override
-            public boolean isVertexMasked (String vertex) {
-                return (vertex == v1);
-            }
-        };
+    private MaskEdgeSet<String, DefaultEdge> testMaskedEdgeSet;
 
     @Override
     protected void setUp () {
-        directed =
+        DirectedGraph<String, DefaultEdge> directed =
             new DefaultDirectedGraph<String, DefaultEdge>(
                 DefaultEdge.class);
 
@@ -87,15 +74,33 @@ protected void setUp () {
         loop1 = directed.addEdge(v1, v1);
         loop2 = directed.addEdge(v4, v4);
 
-        vertexMaskedEdgeSet = new MaskEdgeSet<>(directed, directed.edgeSet(), vertexMaskingFunctor);
+        // Functor that masks vertex v1 and and the edge v2-v3
+        MaskFunctor<String, DefaultEdge> mask = new MaskFunctor<String, DefaultEdge> () {
+                @Override
+                public boolean isEdgeMasked (DefaultEdge edge) {
+                    return (edge == e2);
+                }
+
+                @Override
+                public boolean isVertexMasked (String vertex) {
+                    return (vertex == v1);
+                }
+            };
+
+        testMaskedEdgeSet = new MaskEdgeSet<>(directed, directed.edgeSet(), mask);
     }
 
     // TESTS
     public void testContains () {
-        assertFalse(vertexMaskedEdgeSet.contains(e1));
-        assertTrue(vertexMaskedEdgeSet.contains(e2));
+        assertFalse(testMaskedEdgeSet.contains(e1));
+        assertFalse(testMaskedEdgeSet.contains(e2));
+        assertTrue(testMaskedEdgeSet.contains(e3));
+
+        assertFalse(testMaskedEdgeSet.contains(loop1));
+        assertTrue(testMaskedEdgeSet.contains(loop2));
+    }
 
-        assertFalse(vertexMaskedEdgeSet.contains(loop1));
-        assertTrue(vertexMaskedEdgeSet.contains(loop2));
+    public void testSize () {
+        assertEquals(2, testMaskedEdgeSet.size());
     }
 }

jgrapht-core/src/test/java/org/jgrapht/graph/MaskVertexSetTest.java

@@ -0,0 +1,102 @@
+/* ==========================================
+ * JGraphT : a free Java graph-theory library
+ * ==========================================
+ *
+ * Project Info:  http://jgrapht.sourceforge.net/
+ * Project Creator:  Barak Naveh (http://sourceforge.net/users/barak_naveh)
+ *
+ * (C) Copyright 2003-2008, by Barak Naveh and Contributors.
+ *
+ * This program and the accompanying materials are dual-licensed under
+ * either
+ *
+ * (a) the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation, or (at your option) any
+ * later version.
+ *
+ * or (per the licensee's choosing)
+ *
+ * (b) the terms of the Eclipse Public License v1.0 as published by
+ * the Eclipse Foundation.
+ */
+/* --------------------------
+ * MaskVertexSetTest.java
+ * --------------------------
+ * (C) Copyright 2016-, by Andrew Gainer-Dewar and Contributors.
+ *
+ * Original Author:  Andrew Gainer-Dewar, Ph.D>
+ * Contributor(s):   -
+ *
+ * Changes
+ * -------
+ * April-2016: Initial version;
+ *
+ */
+package org.jgrapht.graph;
+
+import java.util.*;
+
+import org.jgrapht.*;
+
+
+/**
+ * Unit tests for MaskVertexSet.
+ *
+ * @author Andrew Gainer-Dewar
+ */
+public class MaskVertexSetTest
+    extends EnhancedTestCase
+{
+    private DirectedGraph<String, DefaultEdge> directed;
+    private String v1 = "v1";
+    private String v2 = "v2";
+    private String v3 = "v3";
+    private String v4 = "v4";
+    private DefaultEdge e1, e2, e3, loop1, loop2;
+
+    private MaskVertexSet<String, DefaultEdge> testMaskVertexSet;
+
+    @Override
+    protected void setUp () {
+        directed =
+            new DefaultDirectedGraph<String, DefaultEdge>(
+                DefaultEdge.class);
+
+        directed.addVertex(v1);
+        directed.addVertex(v2);
+        directed.addVertex(v3);
+        directed.addVertex(v4);
+
+        e1 = directed.addEdge(v1, v2);
+        e2 = directed.addEdge(v2, v3);
+        e3 = directed.addEdge(v2, v4);
+
+        loop1 = directed.addEdge(v1, v1);
+        loop2 = directed.addEdge(v4, v4);
+
+        // Functor that masks vertex v1 and and the edge v2-v3
+        MaskFunctor<String, DefaultEdge> mask =  new MaskFunctor<String, DefaultEdge> () {
+                @Override
+                public boolean isEdgeMasked (DefaultEdge edge) {
+                    return (edge == e2);
+                }
+
+                @Override
+                public boolean isVertexMasked (String vertex) {
+                    return (vertex == v1);
+                }
+            };
+
+        testMaskVertexSet = new MaskVertexSet<>(directed.vertexSet(), mask);
+    }
+
+    // TESTS
+    public void testContains () {
+        assertFalse(testMaskVertexSet.contains(v1));
+        assertTrue(testMaskVertexSet.contains(v2));
+    }
+
+    public void testSize () {
+        assertEquals(3, testMaskVertexSet.size());
+    }
+}