/*
* 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.
Comparator;
import java.util.
Map;
import java.util.
SortedSet;
import javax.annotation.
Nullable;
/**
* Basic implementation of the {@link SortedSetMultimap} interface. It's a
* wrapper around {@link AbstractMapBasedMultimap} that converts the returned
* collections into sorted sets. The {@link #createCollection} method
* must return a {@code SortedSet}.
*
* @author Jared Levy
*/
@
GwtCompatible
abstract class
AbstractSortedSetMultimap<K, V>
extends
AbstractSetMultimap<K, V> implements
SortedSetMultimap<K, V> {
/**
* Creates a new multimap that uses the provided map.
*
* @param map place to store the mapping from each key to its corresponding
* values
*/
protected
AbstractSortedSetMultimap(
Map<K,
Collection<V>>
map) {
super(
map);
}
@
Override
abstract
SortedSet<V>
createCollection();
@
Override
SortedSet<V>
createUnmodifiableEmptyCollection() {
Comparator<? super V>
comparator =
valueComparator();
if (
comparator == null) {
return
Collections.
unmodifiableSortedSet(
createCollection());
} else {
return
ImmutableSortedSet.
emptySet(
valueComparator());
}
}
// Following Javadoc copied from Multimap and SortedSetMultimap.
/**
* Returns a collection view of all values associated with a key. If no
* mappings in the multimap have the provided key, an empty collection is
* returned.
*
* <p>Changes to the returned collection will update the underlying multimap,
* and vice versa.
*
* <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
* key, this method returns a {@link SortedSet}, instead of the
* {@link Collection} specified in the {@link Multimap} interface.
*/
@
Override public
SortedSet<V>
get(@
Nullable K
key) {
return (
SortedSet<V>) super.get(
key);
}
/**
* Removes all values associated with a given key. The returned collection is
* immutable.
*
* <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
* key, this method returns a {@link SortedSet}, instead of the
* {@link Collection} specified in the {@link Multimap} interface.
*/
@
Override public
SortedSet<V>
removeAll(@
Nullable Object key) {
return (
SortedSet<V>) super.removeAll(
key);
}
/**
* Stores a collection of values with the same key, replacing any existing
* values for that key. The returned collection is immutable.
*
* <p>Because a {@code SortedSetMultimap} has unique sorted values for a given
* key, this method returns a {@link SortedSet}, instead of the
* {@link Collection} specified in the {@link Multimap} interface.
*
* <p>Any duplicates in {@code values} will be stored in the multimap once.
*/
@
Override public
SortedSet<V>
replaceValues(
@
Nullable K
key,
Iterable<? extends V>
values) {
return (
SortedSet<V>) super.replaceValues(
key,
values);
}
/**
* Returns a map view that associates each key with the corresponding values
* in the multimap. Changes to the returned map, such as element removal, will
* update the underlying multimap. The map does not support {@code setValue}
* on its entries, {@code put}, or {@code putAll}.
*
* <p>When passed a key that is present in the map, {@code
* asMap().get(Object)} has the same behavior as {@link #get}, returning a
* live collection. When passed a key that is not present, however, {@code
* asMap().get(Object)} returns {@code null} instead of an empty collection.
*
* <p>Though the method signature doesn't say so explicitly, the returned map
* has {@link SortedSet} values.
*/
@
Override public
Map<K,
Collection<V>>
asMap() {
return super.asMap();
}
/**
* {@inheritDoc}
*
* Consequently, the values do not follow their natural ordering or the
* ordering of the value comparator.
*/
@
Override public
Collection<V>
values() {
return super.values();
}
private static final long
serialVersionUID = 430848587173315748L;
}