001/*
002 * Copyright (C) 2007 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
005 * in compliance with the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the License
010 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
011 * or implied. See the License for the specific language governing permissions and limitations under
012 * the License.
013 */
014
015package com.google.common.base;
016
017import com.google.common.annotations.GwtIncompatible;
018import com.google.errorprone.annotations.DoNotMock;
019
020/**
021 * Implemented by references that have code to run after garbage collection of their referents.
022 *
023 * @see FinalizableReferenceQueue
024 * @author Bob Lee
025 * @since 2.0
026 */
027@DoNotMock("Use an instance of one of the Finalizable*Reference classes")
028@GwtIncompatible
029@ElementTypesAreNonnullByDefault
030public interface FinalizableReference {
031  /**
032   * Invoked on a background thread after the referent has been garbage collected unless security
033   * restrictions prevented starting a background thread, in which case this method is invoked when
034   * new references are created.
035   */
036  void finalizeReferent();
037}