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.Set; 24 25import javax.annotation.Nullable; 26 27/** 28 * Basic implementation of the {@link SetMultimap} interface. It's a wrapper 29 * around {@link AbstractMultimap} that converts the returned collections into 30 * {@code Sets}. The {@link #createCollection} method must return a {@code Set}. 31 * 32 * @author Jared Levy 33 */ 34@GwtCompatible 35abstract class AbstractSetMultimap<K, V> 36 extends AbstractMultimap<K, V> implements SetMultimap<K, V> { 37 /** 38 * Creates a new multimap that uses the provided map. 39 * 40 * @param map place to store the mapping from each key to its corresponding 41 * values 42 */ 43 protected AbstractSetMultimap(Map<K, Collection<V>> map) { 44 super(map); 45 } 46 47 @Override abstract Set<V> createCollection(); 48 49 // Following Javadoc copied from SetMultimap. 50 51 /** 52 * {@inheritDoc} 53 * 54 * <p>Because a {@code SetMultimap} has unique values for a given key, this 55 * method returns a {@link Set}, instead of the {@link Collection} specified 56 * in the {@link Multimap} interface. 57 */ 58 @Override public Set<V> get(@Nullable K key) { 59 return (Set<V>) super.get(key); 60 } 61 62 /** 63 * {@inheritDoc} 64 * 65 * <p>Because a {@code SetMultimap} has unique values for a given key, this 66 * method returns a {@link Set}, instead of the {@link Collection} specified 67 * in the {@link Multimap} interface. 68 */ 69 @Override public Set<Map.Entry<K, V>> entries() { 70 return (Set<Map.Entry<K, V>>) super.entries(); 71 } 72 73 /** 74 * {@inheritDoc} 75 * 76 * <p>Because a {@code SetMultimap} has unique values for a given key, this 77 * method returns a {@link Set}, instead of the {@link Collection} specified 78 * in the {@link Multimap} interface. 79 */ 80 @Override public Set<V> removeAll(@Nullable Object key) { 81 return (Set<V>) super.removeAll(key); 82 } 83 84 /** 85 * {@inheritDoc} 86 * 87 * <p>Because a {@code SetMultimap} has unique values for a given key, this 88 * method returns a {@link Set}, instead of the {@link Collection} specified 89 * in the {@link Multimap} interface. 90 * 91 * <p>Any duplicates in {@code values} will be stored in the multimap once. 92 */ 93 @Override public Set<V> replaceValues( 94 @Nullable K key, Iterable<? extends V> values) { 95 return (Set<V>) super.replaceValues(key, values); 96 } 97 98 /** 99 * {@inheritDoc} 100 * 101 * <p>Though the method signature doesn't say so explicitly, the returned map 102 * has {@link Set} values. 103 */ 104 @Override public Map<K, Collection<V>> asMap() { 105 return super.asMap(); 106 } 107 108 /** 109 * Stores a key-value pair in the multimap. 110 * 111 * @param key key to store in the multimap 112 * @param value value to store in the multimap 113 * @return {@code true} if the method increased the size of the multimap, or 114 * {@code false} if the multimap already contained the key-value pair 115 */ 116 @Override public boolean put(K key, V value) { 117 return super.put(key, value); 118 } 119 120 /** 121 * Compares the specified object to this multimap for equality. 122 * 123 * <p>Two {@code SetMultimap} instances are equal if, for each key, they 124 * contain the same values. Equality does not depend on the ordering of keys 125 * or values. 126 */ 127 @Override public boolean equals(@Nullable Object object) { 128 return super.equals(object); 129 } 130 131 private static final long serialVersionUID = 7431625294878419160L; 132} 133