/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.tools.visualvm.api.caching.impl;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.SoftReference;
/**
* Extended {@linkplain SoftReference} to allow euqals() and hashCode()
* to be computed from the referenced object
*
* @author Jaroslav Bachorik
*/
class SoftReferenceEx<T> extends SoftReference<T> {
private int hashCode;
public SoftReferenceEx(T referent, ReferenceQueue<? super T> q) {
super(referent, q);
hashCode = referent != null ? referent.hashCode() : 0;
}
public SoftReferenceEx(T referent) {
super(referent);
hashCode = referent != null ? referent.hashCode() : 0;
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof SoftReferenceEx)) return false;
SoftReferenceEx other = (SoftReferenceEx)obj;
if (get() == null || other.get() == null) return false;
return get().equals(other.get());
}
@Override
public int hashCode() {
return hashCode;
}
}