com.google.common.collect.AbstractSetMultimap Maven / Gradle / Ivy
/*
* 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.Collections;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
/**
* Basic implementation of the {@link SetMultimap} interface. It's a wrapper around {@link
* AbstractMapBasedMultimap} that converts the returned collections into {@code Sets}. The {@link
* #createCollection} method must return a {@code Set}.
*
* @author Jared Levy
*/
@GwtCompatible
abstract class AbstractSetMultimap extends AbstractMapBasedMultimap
implements SetMultimap {
/**
* Creates a new multimap that uses the provided map.
*
* @param map place to store the mapping from each key to its corresponding values
*/
protected AbstractSetMultimap(Map> map) {
super(map);
}
@Override
abstract Set createCollection();
@Override
Set createUnmodifiableEmptyCollection() {
return Collections.emptySet();
}
@Override
Collection unmodifiableCollectionSubclass(Collection collection) {
return Collections.unmodifiableSet((Set) collection);
}
@Override
Collection wrapCollection(K key, Collection collection) {
return new WrappedSet(key, (Set) collection);
}
// Following Javadoc copied from SetMultimap.
/**
* {@inheritDoc}
*
* Because a {@code SetMultimap} has unique values for a given key, this method returns a
* {@link Set}, instead of the {@link Collection} specified in the {@link Multimap} interface.
*/
@Override
public Set get(K key) {
return (Set) super.get(key);
}
/**
* {@inheritDoc}
*
* Because a {@code SetMultimap} has unique values for a given key, this method returns a
* {@link Set}, instead of the {@link Collection} specified in the {@link Multimap} interface.
*/
@Override
public Set> entries() {
return (Set>) super.entries();
}
/**
* {@inheritDoc}
*
* Because a {@code SetMultimap} has unique values for a given key, this method returns a
* {@link Set}, instead of the {@link Collection} specified in the {@link Multimap} interface.
*/
@Override
public Set removeAll(Object key) {
return (Set) super.removeAll(key);
}
/**
* {@inheritDoc}
*
* Because a {@code SetMultimap} has unique values for a given key, this method returns a
* {@link Set}, instead of the {@link Collection} specified in the {@link Multimap} interface.
*
*
Any duplicates in {@code values} will be stored in the multimap once.
*/
@Override
public Set replaceValues(K key, Iterable values) {
return (Set) super.replaceValues(key, values);
}
/**
* {@inheritDoc}
*
* Though the method signature doesn't say so explicitly, the returned map has {@link Set}
* values.
*/
@Override
public Map> asMap() {
return super.asMap();
}
/**
* Stores a key-value pair in the multimap.
*
* @param key key to store in the multimap
* @param value value to store in the multimap
* @return {@code true} if the method increased the size of the multimap, or {@code false} if the
* multimap already contained the key-value pair
*/
@Override
public boolean put(K key, V value) {
return super.put(key, value);
}
/**
* Compares the specified object to this multimap for equality.
*
* 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.
*/
@Override
public boolean equals(Object object) {
return super.equals(object);
}
private static final long serialVersionUID = 7431625294878419160L;
}