1 /*
   2  * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package test.javafx.collections;
  27 
  28 import com.sun.javafx.binding.SetExpressionHelper;
  29 import com.sun.javafx.collections.ObservableSetWrapper;
  30 import org.junit.Test;
  31 
  32 import java.util.HashSet;
  33 import javafx.collections.SetChangeListener;
  34 import javafx.collections.WeakSetChangeListener;
  35 
  36 import static org.junit.Assert.*;
  37 
  38 public class WeakSetChangeListenerTest {
  39         
  40     @Test(expected=NullPointerException.class)
  41     public void testConstructWithNull() {
  42         new WeakSetChangeListener<Object>(null);
  43     }
  44 
  45     @Test
  46     public void testHandle() {
  47         MockSetObserver<Object> listener = new MockSetObserver<Object>();
  48         final WeakSetChangeListener<Object> weakListener = new WeakSetChangeListener<Object>(listener);
  49         final ObservableSetMock set = new ObservableSetMock();
  50         final Object removedElement = new Object();
  51         final SetChangeListener.Change<Object> change = new SetExpressionHelper.SimpleChange<Object>(set).setRemoved(removedElement);
  52 
  53         // regular call
  54         weakListener.onChanged(change);
  55         listener.assertRemoved(MockSetObserver.Tuple.tup(removedElement));
  56         assertFalse(weakListener.wasGarbageCollected());
  57 
  58         // GC-ed call
  59         set.reset();
  60         listener = null;
  61         System.gc();
  62         assertTrue(weakListener.wasGarbageCollected());
  63         weakListener.onChanged(change);
  64         assertEquals(1, set.removeCounter);
  65     }
  66 
  67     private static class ObservableSetMock extends ObservableSetWrapper<Object> {
  68         private int removeCounter;
  69 
  70         public ObservableSetMock() {
  71             super(new HashSet<Object>());
  72         }
  73 
  74         private void reset() {
  75             removeCounter = 0;
  76         }
  77 
  78         @Override
  79                 public void removeListener(SetChangeListener<? super Object> listener) {
  80             removeCounter++;
  81                 }
  82     }
  83 
  84 }