001/* 002 * Copyright (C) 2010 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package com.google.common.collect; 018 019import com.google.common.annotations.GwtCompatible; 020import com.google.errorprone.annotations.CanIgnoreReturnValue; 021import java.util.List; 022import javax.annotation.Nullable; 023 024/** 025 * A list multimap which forwards all its method calls to another list multimap. 026 * Subclasses should override one or more methods to modify the behavior of 027 * the backing multimap as desired per the <a 028 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 029 * 030 * @author Kurt Alfred Kluever 031 * @since 3.0 032 */ 033@GwtCompatible 034public abstract class ForwardingListMultimap<K, V> extends ForwardingMultimap<K, V> 035 implements ListMultimap<K, V> { 036 037 /** Constructor for use by subclasses. */ 038 protected ForwardingListMultimap() {} 039 040 @Override 041 protected abstract ListMultimap<K, V> delegate(); 042 043 @Override 044 public List<V> get(@Nullable K key) { 045 return delegate().get(key); 046 } 047 048 @CanIgnoreReturnValue 049 @Override 050 public List<V> removeAll(@Nullable Object key) { 051 return delegate().removeAll(key); 052 } 053 054 @CanIgnoreReturnValue 055 @Override 056 public List<V> replaceValues(K key, Iterable<? extends V> values) { 057 return delegate().replaceValues(key, values); 058 } 059}