1 /* 2 * Copyright (C) 2007 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.base; 18 19 import java.lang.ref.WeakReference; 20 21 /** 22 * Weak reference with a {@code finalizeReferent()} method which a background 23 * thread invokes after the garbage collector reclaims the referent. This is a 24 * simpler alternative to using a {@link java.lang.ref.ReferenceQueue}. 25 * 26 * @author Bob Lee 27 * @since 2010.01.04 <b>stable</b> (imported from Google Collections Library) 28 */ 29 public abstract class FinalizableWeakReference<T> extends WeakReference<T> 30 implements FinalizableReference { 31 32 /** 33 * Constructs a new finalizable weak reference. 34 * 35 * @param referent to weakly reference 36 * @param queue that should finalize the referent 37 */ 38 protected FinalizableWeakReference(T referent, 39 FinalizableReferenceQueue queue) { 40 super(referent, queue.queue); 41 queue.cleanUp(); 42 } 43 } 44
