An extension of WeakReference that implements a sane equals and hashcode method.
/*
* Copyright (c) 2006-2008 Chris Smith, Shane Mc Cormack, Gregory Holmes
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
//package com.dmdirc.util;
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
/**
* An extension of WeakReference that implements a sane equals and hashcode
* method.
*
* @param <T> The type of object that this reference contains
* @author chris
*/
public class EquatableWeakReference<T> extends WeakReference<T> {
/**
* Creates a new instance of EquatableWeakReference.
*
* @param referent The object that this weak reference should reference.
*/
public EquatableWeakReference(T referent) {
super(referent);
}
/** {@inheritDoc} */
@Override
public boolean equals(Object obj) {
if (obj instanceof Reference) {
return get().equals(((Reference) obj).get());
} else {
return get().equals(obj);
}
}
/** {@inheritDoc} */
@Override
public int hashCode() {
return get().hashCode();
}
}
/*
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import org.junit.Test;
import static org.junit.Assert.*;
public class EquatableWeakReferenceTest extends junit.framework.TestCase {
@Test
public void testEquals() {
final Object myObject = "moo";
final Reference<Object> myRef = new WeakReference<Object>(myObject);
final EquatableWeakReference<Object> ewf = new EquatableWeakReference<Object>(myObject);
assertTrue(ewf.equals(myObject));
assertTrue(ewf.equals(myRef));
assertFalse(ewf.equals("bar"));
assertFalse(ewf.equals(new WeakReference<Object>("bar")));
}
@Test
public void testHashCode() {
final Object myObject = "moo";
final EquatableWeakReference<Object> ewf = new EquatableWeakReference<Object>(myObject);
assertEquals(myObject.hashCode(), ewf.hashCode());
}
}
*/
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