1 /* 2 * Copyright (C) 2007 Google Inc. 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.Collection; 22 import java.util.Map; 23 import java.util.Set; 24 25 import javax.annotation.Nullable; 26 27 /** 28 * A {@code Multimap} that cannot hold duplicate key-value pairs. Adding a 29 * key-value pair that's already in the multimap has no effect. 30 * 31 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods 32 * each return a {@link Set} of values, while {@link #entries} returns a {@code 33 * Set} of map entries. Though the method signature doesn't say so explicitly, 34 * the map returned by {@link #asMap} has {@code Set} values. 35 * 36 * @author Jared Levy 37 * @since 2010.01.04 <b>stable</b> (imported from Google Collections Library) 38 */ 39 @GwtCompatible 40 public interface SetMultimap<K, V> extends Multimap<K, V> { 41 /** 42 * {@inheritDoc} 43 * 44 * <p>Because a {@code SetMultimap} has unique values for a given key, this 45 * method returns a {@link Set}, instead of the {@link java.util.Collection} 46 * specified in the {@link Multimap} interface. 47 */ 48 Set<V> get(@Nullable K key); 49 50 /** 51 * {@inheritDoc} 52 * 53 * <p>Because a {@code SetMultimap} has unique values for a given key, this 54 * method returns a {@link Set}, instead of the {@link java.util.Collection} 55 * specified in the {@link Multimap} interface. 56 */ 57 Set<V> removeAll(@Nullable Object key); 58 59 /** 60 * {@inheritDoc} 61 * 62 * <p>Because a {@code SetMultimap} has unique values for a given key, this 63 * method returns a {@link Set}, instead of the {@link java.util.Collection} 64 * specified in the {@link Multimap} interface. 65 * 66 * <p>Any duplicates in {@code values} will be stored in the multimap once. 67 */ 68 Set<V> replaceValues(K key, Iterable<? extends V> values); 69 70 /** 71 * {@inheritDoc} 72 * 73 * <p>Because a {@code SetMultimap} has unique values for a given key, this 74 * method returns a {@link Set}, instead of the {@link java.util.Collection} 75 * specified in the {@link Multimap} interface. 76 */ 77 Set<Map.Entry<K, V>> entries(); 78 79 /** 80 * {@inheritDoc} 81 * 82 * <p>Though the method signature doesn't say so explicitly, the returned map 83 * has {@link Set} values. 84 */ 85 Map<K, Collection<V>> asMap(); 86 87 /** 88 * Compares the specified object to this multimap for equality. 89 * 90 * <p>Two {@code SetMultimap} instances are equal if, for each key, they 91 * contain the same values. Equality does not depend on the ordering of keys 92 * or values. 93 */ 94 boolean equals(@Nullable Object obj); 95 } 96
