001 /*
002 * Copyright (C) 2007 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
017 package com.google.common.collect;
018
019 import com.google.common.annotations.GwtCompatible;
020
021 import java.util.Collection;
022 import java.util.List;
023 import java.util.Map;
024
025 import javax.annotation.Nullable;
026
027 /**
028 * A {@code Multimap} that can hold duplicate key-value pairs and that maintains
029 * the insertion ordering of values for a given key. See the {@link Multimap}
030 * documentation for information common to all multimaps.
031 *
032 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods
033 * each return a {@link List} of values. Though the method signature doesn't say
034 * so explicitly, the map returned by {@link #asMap} has {@code List} values.
035 *
036 * <p>See the Guava User Guide article on <a href=
037 * "http://code.google.com/p/guava-libraries/wiki/NewCollectionTypesExplained#Multimap">
038 * {@code Multimap}</a>.
039 *
040 * @author Jared Levy
041 * @since 2.0 (imported from Google Collections Library)
042 */
043 @GwtCompatible
044 public interface ListMultimap<K, V> extends Multimap<K, V> {
045 /**
046 * {@inheritDoc}
047 *
048 * <p>Because the values for a given key may have duplicates and follow the
049 * insertion ordering, this method returns a {@link List}, instead of the
050 * {@link java.util.Collection} specified in the {@link Multimap} interface.
051 */
052 @Override
053 List<V> get(@Nullable K key);
054
055 /**
056 * {@inheritDoc}
057 *
058 * <p>Because the values for a given key may have duplicates and follow the
059 * insertion ordering, this method returns a {@link List}, instead of the
060 * {@link java.util.Collection} specified in the {@link Multimap} interface.
061 */
062 @Override
063 List<V> removeAll(@Nullable Object key);
064
065 /**
066 * {@inheritDoc}
067 *
068 * <p>Because the values for a given key may have duplicates and follow the
069 * insertion ordering, this method returns a {@link List}, instead of the
070 * {@link java.util.Collection} specified in the {@link Multimap} interface.
071 */
072 @Override
073 List<V> replaceValues(K key, Iterable<? extends V> values);
074
075 /**
076 * {@inheritDoc}
077 *
078 * <p>Though the method signature doesn't say so explicitly, the returned map
079 * has {@link List} values.
080 */
081 @Override
082 Map<K, Collection<V>> asMap();
083
084 /**
085 * Compares the specified object to this multimap for equality.
086 *
087 * <p>Two {@code ListMultimap} instances are equal if, for each key, they
088 * contain the same values in the same order. If the value orderings disagree,
089 * the multimaps will not be considered equal.
090 *
091 * <p>An empty {@code ListMultimap} is equal to any other empty {@code
092 * Multimap}, including an empty {@code SetMultimap}.
093 */
094 @Override
095 boolean equals(@Nullable Object obj);
096 }