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 017package com.google.common.collect; 018 019import com.google.common.annotations.GwtCompatible; 020import com.google.errorprone.annotations.CanIgnoreReturnValue; 021import java.util.Collection; 022import java.util.Comparator; 023import java.util.Map; 024import java.util.Set; 025import java.util.SortedMap; 026import java.util.SortedSet; 027import org.checkerframework.checker.nullness.qual.Nullable; 028 029/** 030 * A {@code SetMultimap} whose set of values for a given key are kept sorted; that is, they comprise 031 * a {@link SortedSet}. It cannot hold duplicate key-value pairs; adding a key-value pair that's 032 * already in the multimap has no effect. This interface does not specify the ordering of the 033 * multimap's keys. See the {@link Multimap} documentation for information common to all multimaps. 034 * 035 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods each return a {@link 036 * SortedSet} of values, while {@link Multimap#entries()} returns a {@link Set} of map entries. 037 * Though the method signature doesn't say so explicitly, the map returned by {@link #asMap} has 038 * {@code SortedSet} values. 039 * 040 * <p>See the Guava User Guide article on <a href= 041 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multimap"> {@code 042 * Multimap}</a>. 043 * 044 * @author Jared Levy 045 * @since 2.0 046 */ 047@GwtCompatible 048public interface SortedSetMultimap<K, V> extends SetMultimap<K, V> { 049 // Following Javadoc copied from Multimap. 050 051 /** 052 * Returns a collection view of all values associated with a key. If no mappings in the multimap 053 * have the provided key, an empty collection is returned. 054 * 055 * <p>Changes to the returned collection will update the underlying multimap, and vice versa. 056 * 057 * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method 058 * returns a {@link SortedSet}, instead of the {@link java.util.Collection} specified in the 059 * {@link Multimap} interface. 060 */ 061 @Override 062 SortedSet<V> get(@Nullable K key); 063 064 /** 065 * Removes all values associated with a given key. 066 * 067 * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method 068 * returns a {@link SortedSet}, instead of the {@link java.util.Collection} specified in the 069 * {@link Multimap} interface. 070 */ 071 @CanIgnoreReturnValue 072 @Override 073 SortedSet<V> removeAll(@Nullable Object key); 074 075 /** 076 * Stores a collection of values with the same key, replacing any existing values for that key. 077 * 078 * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method 079 * returns a {@link SortedSet}, instead of the {@link java.util.Collection} specified in the 080 * {@link Multimap} interface. 081 * 082 * <p>Any duplicates in {@code values} will be stored in the multimap once. 083 */ 084 @CanIgnoreReturnValue 085 @Override 086 SortedSet<V> replaceValues(K key, Iterable<? extends V> values); 087 088 /** 089 * Returns a map view that associates each key with the corresponding values in the multimap. 090 * Changes to the returned map, such as element removal, will update the underlying multimap. The 091 * map does not support {@code setValue()} on its entries, {@code put}, or {@code putAll}. 092 * 093 * <p>When passed a key that is present in the map, {@code asMap().get(Object)} has the same 094 * behavior as {@link #get}, returning a live collection. When passed a key that is not present, 095 * however, {@code asMap().get(Object)} returns {@code null} instead of an empty collection. 096 * 097 * <p><b>Note:</b> The returned map's values are guaranteed to be of type {@link SortedSet}. To 098 * obtain this map with the more specific generic type {@code Map<K, SortedSet<V>>}, call {@link 099 * Multimaps#asMap(SortedSetMultimap)} instead. <b>However</b>, the returned map <i>itself</i> is 100 * not necessarily a {@link SortedMap}: A {@code SortedSetMultimap} must expose the <i>values</i> 101 * for a given key in sorted order, but it need not expose the <i>keys</i> in sorted order. 102 * Individual {@code SortedSetMultimap} implementations, like those built with {@link 103 * MultimapBuilder#treeKeys()}, may make additional guarantees. 104 */ 105 @Override 106 Map<K, Collection<V>> asMap(); 107 108 /** 109 * Returns the comparator that orders the multimap values, with {@code null} indicating that 110 * natural ordering is used. 111 */ 112 Comparator<? super V> valueComparator(); 113}