/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.collections.map;
import java.lang.ref.WeakReference;
import java.util.Map;
import junit.framework.Test;
import org.apache.commons.collections.BulkTest;
/**
* Tests for ReferenceMap.
*
* @version $Revision: 646780 $ $Date: 2008-04-10 13:48:07 +0100 (Thu, 10 Apr 2008) $
*
* @author Paul Jack
* @author Guilhem Lavaux
*/
public class TestReferenceMap extends AbstractTestIterableMap {
public TestReferenceMap(String testName) {
super(testName);
}
public static Test suite() {
return BulkTest.makeSuite(TestReferenceMap.class);
}
public static void main(String args[]) {
String[] testCaseName = { TestReferenceMap.class.getName() };
junit.textui.TestRunner.main(testCaseName);
}
public Map makeEmptyMap() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
return map;
}
public boolean isAllowNullKey() {
return false;
}
public boolean isAllowNullValue() {
return false;
}
public String getCompatibilityVersion() {
return "3.1";
}
//-----------------------------------------------------------------------
public void testNullHandling() {
resetFull();
assertEquals(null, map.get(null));
assertEquals(false, map.containsKey(null));
assertEquals(false, map.containsValue(null));
assertEquals(null, map.remove(null));
assertEquals(false, map.entrySet().contains(null));
assertEquals(false, map.keySet().contains(null));
assertEquals(false, map.values().contains(null));
try {
map.put(null, null);
fail();
} catch (NullPointerException ex) {}
try {
map.put(new Object(), null);
fail();
} catch (NullPointerException ex) {}
try {
map.put(null, new Object());
fail();
} catch (NullPointerException ex) {}
}
//-----------------------------------------------------------------------
/*
// Tests often fail because gc is uncontrollable
public void testPurge() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
Object[] hard = new Object[10];
for (int i = 0; i < hard.length; i++) {
hard[i] = new Object();
map.put(hard[i], new Object());
}
gc();
assertTrue("map should be empty after purge of weak values", map.isEmpty());
for (int i = 0; i < hard.length; i++) {
map.put(new Object(), hard[i]);
}
gc();
assertTrue("map should be empty after purge of weak keys", map.isEmpty());
for (int i = 0; i < hard.length; i++) {
map.put(new Object(), hard[i]);
map.put(hard[i], new Object());
}
gc();
assertTrue("map should be empty after purge of weak keys and values", map.isEmpty());
}
public void testGetAfterGC() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
for (int i = 0; i < 10; i++) {
map.put(new Integer(i), new Integer(i));
}
gc();
for (int i = 0; i < 10; i++) {
Integer I = new Integer(i);
assertTrue("map.containsKey should return false for GC'd element", !map.containsKey(I));
assertTrue("map.get should return null for GC'd element", map.get(I) == null);
}
}
public void testEntrySetIteratorAfterGC() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
Object[] hard = new Object[10];
for (int i = 0; i < 10; i++) {
hard[i] = new Integer(10 + i);
map.put(new Integer(i), new Integer(i));
map.put(hard[i], hard[i]);
}
gc();
Iterator iterator = map.entrySet().iterator();
while (iterator.hasNext()) {
Map.Entry entry = (Map.Entry)iterator.next();
Integer key = (Integer)entry.getKey();
Integer value = (Integer)entry.getValue();
assertTrue("iterator should skip GC'd keys", key.intValue() >= 10);
assertTrue("iterator should skip GC'd values", value.intValue() >= 10);
}
}
public void testMapIteratorAfterGC() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
Object[] hard = new Object[10];
for (int i = 0; i < 10; i++) {
hard[i] = new Integer(10 + i);
map.put(new Integer(i), new Integer(i));
map.put(hard[i], hard[i]);
}
gc();
MapIterator iterator = map.mapIterator();
while (iterator.hasNext()) {
Object key1 = iterator.next();
Integer key = (Integer) iterator.getKey();
Integer value = (Integer) iterator.getValue();
assertTrue("iterator keys should match", key == key1);
assertTrue("iterator should skip GC'd keys", key.intValue() >= 10);
assertTrue("iterator should skip GC'd values", value.intValue() >= 10);
}
}
public void testMapIteratorAfterGC2() {
ReferenceMap map = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.WEAK);
Object[] hard = new Object[10];
for (int i = 0; i < 10; i++) {
hard[i] = new Integer(10 + i);
map.put(new Integer(i), new Integer(i));
map.put(hard[i], hard[i]);
}
MapIterator iterator = map.mapIterator();
while (iterator.hasNext()) {
Object key1 = iterator.next();
gc();
Integer key = (Integer) iterator.getKey();
Integer value = (Integer) iterator.getValue();
assertTrue("iterator keys should match", key == key1);
assertTrue("iterator should skip GC'd keys", key.intValue() >= 10);
assertTrue("iterator should skip GC'd values", value.intValue() >= 10);
}
}
*/
WeakReference keyReference;
WeakReference valueReference;
public Map buildRefMap() {
Object key = new Object();
Object value = new Object();
keyReference = new WeakReference(key);
valueReference = new WeakReference(value);
Map testMap = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.HARD, true);
testMap.put(key, value);
assertEquals("In map", value, testMap.get(key));
assertNotNull("Weak reference released early (1)", keyReference.get());
assertNotNull("Weak reference released early (2)", valueReference.get());
return testMap;
}
/** Tests whether purge values setting works */
public void testPurgeValues() throws Exception {
// many thanks to Juozas Baliuka for suggesting this method
Map testMap = buildRefMap();
int iterations = 0;
int bytz = 2;
while(true) {
System.gc();
if(iterations++ > 50){
fail("Max iterations reached before resource released.");
}
testMap.isEmpty();
if(
keyReference.get() == null &&
valueReference.get() == null) {
break;
} else {
// create garbage:
byte[] b = new byte[bytz];
bytz = bytz * 2;
}
}
}
private static void gc() {
try {
// trigger GC
byte[][] tooLarge = new byte[1000000000][1000000000];
fail("you have too much RAM");
} catch (OutOfMemoryError ex) {
System.gc(); // ignore
}
}
}