1   /*
2    * Copyright (C) 2010 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.List;
22  
23  import javax.annotation.Nullable;
24  
25  /**
26   * A list multimap which forwards all its method calls to another list multimap.
27   * Subclasses should override one or more methods to modify the behavior of
28   * the backing multimap as desired per the <a
29   * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
30   *
31   * @author Kurt Alfred Kluever
32   * @since 3.0
33   */
34  @GwtCompatible
35  public abstract class ForwardingListMultimap<K, V>
36      extends ForwardingMultimap<K, V> implements ListMultimap<K, V> {
37  
38    /** Constructor for use by subclasses. */
39    protected ForwardingListMultimap() {}
40  
41    @Override protected abstract ListMultimap<K, V> delegate();
42  
43    @Override public List<V> get(@Nullable K key) {
44      return delegate().get(key);
45    }
46  
47    @Override public List<V> removeAll(@Nullable Object key) {
48      return delegate().removeAll(key);
49    }
50  
51    @Override public List<V> replaceValues(K key, Iterable<? extends V> values) {
52      return delegate().replaceValues(key, values);
53    }
54  }