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.common.annotations.J2ktIncompatible;
019import com.google.errorprone.annotations.DoNotMock;
020
021/**
022 * Implemented by references that have code to run after garbage collection of their referents.
023 *
024 * @see FinalizableReferenceQueue
025 * @author Bob Lee
026 * @since 2.0
027 */
028@DoNotMock("Use an instance of one of the Finalizable*Reference classes")
029@J2ktIncompatible
030@GwtIncompatible
031@ElementTypesAreNonnullByDefault
032public interface FinalizableReference {
033  /**
034   * Invoked on a background thread after the referent has been garbage collected unless security
035   * restrictions prevented starting a background thread, in which case this method is invoked when
036   * new references are created.
037   */
038  void finalizeReferent();
039}