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
17package com.google.common.collect;
18
19import com.google.common.annotations.GwtCompatible;
20
21import java.util.Collection;
22import java.util.Map;
23import java.util.SortedSet;
24
25import javax.annotation.Nullable;
26
27/**
28 * Basic implementation of the {@link SortedSetMultimap} interface. It's a
29 * wrapper around {@link AbstractMultimap} that converts the returned
30 * collections into sorted sets. The {@link #createCollection} method
31 * must return a {@code SortedSet}.
32 *
33 * @author Jared Levy
34 */
35@GwtCompatible
36abstract class AbstractSortedSetMultimap<K, V>
37    extends AbstractSetMultimap<K, V> implements SortedSetMultimap<K, V> {
38  /**
39   * Creates a new multimap that uses the provided map.
40   *
41   * @param map place to store the mapping from each key to its corresponding
42   *     values
43   */
44  protected AbstractSortedSetMultimap(Map<K, Collection<V>> map) {
45    super(map);
46  }
47
48  @Override abstract SortedSet<V> createCollection();
49
50  // Following Javadoc copied from Multimap and SortedSetMultimap.
51
52  /**
53   * Returns a collection view of all values associated with a key. If no
54   * mappings in the multimap have the provided key, an empty collection is
55   * returned.
56   *
57   * <p>Changes to the returned collection will update the underlying multimap,
58   * and vice versa.
59   *
60   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
61   * key, this method returns a {@link SortedSet}, instead of the
62   * {@link Collection} specified in the {@link Multimap} interface.
63   */
64  @Override public SortedSet<V> get(@Nullable K key) {
65    return (SortedSet<V>) super.get(key);
66  }
67
68  /**
69   * Removes all values associated with a given key. The returned collection is
70   * immutable.
71   *
72   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
73   * key, this method returns a {@link SortedSet}, instead of the
74   * {@link Collection} specified in the {@link Multimap} interface.
75   */
76  @Override public SortedSet<V> removeAll(@Nullable Object key) {
77    return (SortedSet<V>) super.removeAll(key);
78  }
79
80  /**
81   * Stores a collection of values with the same key, replacing any existing
82   * values for that key. The returned collection is immutable.
83   *
84   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
85   * key, this method returns a {@link SortedSet}, instead of the
86   * {@link Collection} specified in the {@link Multimap} interface.
87   *
88   * <p>Any duplicates in {@code values} will be stored in the multimap once.
89   */
90  @Override public SortedSet<V> replaceValues(
91      K key, Iterable<? extends V> values) {
92    return (SortedSet<V>) super.replaceValues(key, values);
93  }
94
95  /**
96   * Returns a map view that associates each key with the corresponding values
97   * in the multimap. Changes to the returned map, such as element removal, will
98   * update the underlying multimap. The map does not support {@code setValue}
99   * on its entries, {@code put}, or {@code putAll}.
100   *
101   * <p>When passed a key that is present in the map, {@code
102   * asMap().get(Object)} has the same behavior as {@link #get}, returning a
103   * live collection. When passed a key that is not present, however, {@code
104   * asMap().get(Object)} returns {@code null} instead of an empty collection.
105   *
106   * <p>Though the method signature doesn't say so explicitly, the returned map
107   * has {@link SortedSet} values.
108   */
109  @Override public Map<K, Collection<V>> asMap() {
110    return super.asMap();
111  }
112
113  /**
114   * {@inheritDoc}
115   *
116   * Consequently, the values do not follow their natural ordering or the
117   * ordering of the value comparator.
118   */
119  @Override public Collection<V> values() {
120    return super.values();
121  }
122
123  private static final long serialVersionUID = 430848587173315748L;
124}
125