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