1 /* 2 * Copyright (C) 2007 The Guava Authors 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.collect; 18 19 import com.google.common.annotations.GwtCompatible; 20 21 import java.util.concurrent.ConcurrentMap; 22 23 /** 24 * A concurrent map which forwards all its method calls to another concurrent 25 * map. Subclasses should override one or more methods to modify the behavior of 26 * the backing map as desired per the <a 27 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 28 * 29 * @author Charles Fry 30 * @since 2.0 (imported from Google Collections Library) 31 */ 32 @GwtCompatible 33 public abstract class ForwardingConcurrentMap<K, V> extends ForwardingMap<K, V> 34 implements ConcurrentMap<K, V> { 35 36 /** Constructor for use by subclasses. */ ForwardingConcurrentMap()37 protected ForwardingConcurrentMap() {} 38 delegate()39 @Override protected abstract ConcurrentMap<K, V> delegate(); 40 41 @Override putIfAbsent(K key, V value)42 public V putIfAbsent(K key, V value) { 43 return delegate().putIfAbsent(key, value); 44 } 45 46 @Override remove(Object key, Object value)47 public boolean remove(Object key, Object value) { 48 return delegate().remove(key, value); 49 } 50 51 @Override replace(K key, V value)52 public V replace(K key, V value) { 53 return delegate().replace(key, value); 54 } 55 56 @Override replace(K key, V oldValue, V newValue)57 public boolean replace(K key, V oldValue, V newValue) { 58 return delegate().replace(key, oldValue, newValue); 59 } 60 61 } 62