/* * 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 com.google.common.annotations.GwtCompatible; import java.util.Collection; import java.util.Map; import java.util.Set; import javax.annotation.Nullable; /** * A {@code Multimap} that cannot hold duplicate key-value pairs. Adding a * key-value pair that's already in the multimap has no effect. See the {@link * Multimap} documentation for information common to all multimaps. * *
The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods * each return a {@link Set} of values, while {@link #entries} returns a {@code * Set} of map entries. Though the method signature doesn't say so explicitly, * the map returned by {@link #asMap} has {@code Set} values. * *
If the values corresponding to a single key should be ordered according to * a {@link java.util.Comparator} (or the natural order), see the * {@link SortedSetMultimap} subinterface. * *
Since the value collections are sets, the behavior of a {@code SetMultimap} * is not specified if key or value objects already present in the * multimap change in a manner that affects {@code equals} comparisons. * Use caution if mutable objects are used as keys or values in a * {@code SetMultimap}. * *
See the Guava User Guide article on
* {@code Multimap}.
*
* @author Jared Levy
* @since 2.0 (imported from Google Collections Library)
*/
@GwtCompatible
public interface SetMultimap Because a {@code SetMultimap} has unique values for a given key, this
* method returns a {@link Set}, instead of the {@link java.util.Collection}
* specified in the {@link Multimap} interface.
*/
@Override
Set Because a {@code SetMultimap} has unique values for a given key, this
* method returns a {@link Set}, instead of the {@link java.util.Collection}
* specified in the {@link Multimap} interface.
*/
@Override
Set Because a {@code SetMultimap} has unique values for a given key, this
* method returns a {@link Set}, instead of the {@link java.util.Collection}
* specified in the {@link Multimap} interface.
*
* Any duplicates in {@code values} will be stored in the multimap once.
*/
@Override
Set Because a {@code SetMultimap} has unique values for a given key, this
* method returns a {@link Set}, instead of the {@link java.util.Collection}
* specified in the {@link Multimap} interface.
*/
@Override
Set Note: The returned map's values are guaranteed to be of type
* {@link Set}. To obtain this map with the more specific generic type
* {@code Map Two {@code SetMultimap} instances are equal if, for each key, they
* contain the same values. Equality does not depend on the ordering of keys
* or values.
*
* An empty {@code SetMultimap} is equal to any other empty {@code
* Multimap}, including an empty {@code ListMultimap}.
*/
@Override
boolean equals(@Nullable Object obj);
}