/* * Copyright (C) 2007 The Guava Authors * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.google.common.collect; import static com.google.common.base.Preconditions.checkNotNull; import com.google.common.annotations.GwtCompatible; import java.util.Collection; import java.util.Comparator; import java.util.SortedMap; import java.util.SortedSet; import java.util.TreeMap; import java.util.TreeSet; /** * Implementation of {@code Multimap} whose keys and values are ordered by * their natural ordering or by supplied comparators. In all cases, this * implementation uses {@link Comparable#compareTo} or {@link * Comparator#compare} instead of {@link Object#equals} to determine * equivalence of instances. * *
Warning: The comparators or comparables used must be consistent * with equals as explained by the {@link Comparable} class specification. * Otherwise, the resulting multiset will violate the general contract of {@link * SetMultimap}, which it is specified in terms of {@link Object#equals}. * *
The collections returned by {@code keySet} and {@code asMap} iterate * through the keys according to the key comparator ordering or the natural * ordering of the keys. Similarly, {@code get}, {@code removeAll}, and {@code * replaceValues} return collections that iterate through the values according * to the value comparator ordering or the natural ordering of the values. The * collections generated by {@code entries}, {@code keys}, and {@code values} * iterate across the keys according to the above key ordering, and for each * key they iterate across the values according to the value ordering. * *
The multimap does not store duplicate key-value pairs. Adding a new * key-value pair equal to an existing key-value pair has no effect. * *
Null keys and values are permitted (provided, of course, that the * respective comparators support them). All optional multimap methods are * supported, and all returned views are modifiable. * *
This class is not threadsafe when any concurrent operations update the
* multimap. Concurrent read operations will work correctly. To allow concurrent
* update operations, wrap your multimap with a call to {@link
* Multimaps#synchronizedSortedSetMultimap}.
*
* @author Jared Levy
* @since 2.0 (imported from Google Collections Library)
*/
@GwtCompatible(serializable = true, emulated = true)
public class TreeMultimap Creates an empty {@code TreeSet} for a collection of values for one key.
*
* @return a new {@code TreeSet} containing a collection of values for one
* key
*/
@Override SortedSet Because a {@code TreeMultimap} has unique sorted keys, this method
* returns a {@link SortedSet}, instead of the {@link java.util.Set} specified
* in the {@link Multimap} interface.
*/
@Override public SortedSet Because a {@code TreeMultimap} has unique sorted keys, this method
* returns a {@link SortedMap}, instead of the {@link java.util.Map} specified
* in the {@link Multimap} interface.
*/
@Override public SortedMap