com.google.common.collect

Interface SortedSetMultimap<K,V>

All Superinterfaces:

Multimap<K,V>, SetMultimap<K,V>

All Known Implementing Classes:

ForwardingSortedSetMultimap, TreeMultimap

@GwtCompatible
public interface SortedSetMultimap<K,V>
extends SetMultimap<K,V>

A SetMultimap whose set of values for a given key are kept sorted; that is, they comprise a SortedSet. It cannot hold duplicate key-value pairs; adding a key-value pair that's already in the multimap has no effect. This interface does not specify the ordering of the multimap's keys. See the Multimap documentation for information common to all multimaps.

The get(K), removeAll(java.lang.Object), and replaceValues(K, java.lang.Iterable<? extends V>) methods each return a SortedSet of values, while Multimap.entries() returns a Set of map entries. Though the method signature doesn't say so explicitly, the map returned by asMap() has SortedSet values.

See the Guava User Guide article on Multimap.

Since:

2.0

Author:

Jared Levy

Method Summary

Modifier and Type	Method and Description
Map<K,Collection<V>>	asMap() Returns a map view that associates each key with the corresponding values in the multimap.
SortedSet<V>	get(K key) Returns a collection view of all values associated with a key.
SortedSet<V>	removeAll(@Nullable Object key) Removes all values associated with a given key.
SortedSet<V>	replaceValues(K key, Iterable<? extends V> values) Stores a collection of values with the same key, replacing any existing values for that key.
Comparator<? super V>	valueComparator() Returns the comparator that orders the multimap values, with null indicating that natural ordering is used.

Methods inherited from interface com.google.common.collect.SetMultimap

entries, equals

Methods inherited from interface com.google.common.collect.Multimap

clear, containsEntry, containsKey, containsValue, forEach, hashCode, isEmpty, keys, keySet, put, putAll, putAll, remove, size, values

Method Detail

get

SortedSet<V> get(K key)

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.

Changes to the returned collection will update the underlying multimap, and vice versa.

Because a SortedSetMultimap has unique sorted values for a given key, this method returns a SortedSet, instead of the Collection specified in the Multimap interface.

Specified by:

get in interface Multimap<K,V>

Specified by:

get in interface SetMultimap<K,V>

removeAll

@CanIgnoreReturnValue
SortedSet<V> removeAll(@Nullable Object key)

Removes all values associated with a given key.

Because a SortedSetMultimap has unique sorted values for a given key, this method returns a SortedSet, instead of the Collection specified in the Multimap interface.

Specified by:

removeAll in interface Multimap<K,V>

Specified by:

removeAll in interface SetMultimap<K,V>

Returns:

the values that were removed (possibly empty). The returned collection may be modifiable, but updating it will have no effect on the multimap.

replaceValues

@CanIgnoreReturnValue
SortedSet<V> replaceValues(K key,
                                                 Iterable<? extends V> values)

Stores a collection of values with the same key, replacing any existing values for that key.

Because a SortedSetMultimap has unique sorted values for a given key, this method returns a SortedSet, instead of the Collection specified in the Multimap interface.

Any duplicates in values will be stored in the multimap once.

Specified by:

replaceValues in interface Multimap<K,V>

Specified by:

replaceValues in interface SetMultimap<K,V>

Returns:

the collection of replaced values, or an empty collection if no values were previously associated with the key. The collection may be modifiable, but updating it will have no effect on the multimap.

asMap

Map<K,Collection<V>> asMap()

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 setValue() on its entries, put, or putAll.

When passed a key that is present in the map, asMap().get(Object) has the same behavior as get(K), returning a live collection. When passed a key that is not present, however, asMap().get(Object) returns null instead of an empty collection.

Note: The returned map's values are guaranteed to be of type SortedSet. To obtain this map with the more specific generic type Map<K, SortedSet<V>>, call Multimaps.asMap(SortedSetMultimap) instead. However, the returned map itself is not necessarily a SortedMap: A SortedSetMultimap must expose the values for a given key in sorted order, but it need not expose the keys in sorted order. Individual SortedSetMultimap implementations, like those built with MultimapBuilder.treeKeys(), may make additional guarantees.

Specified by:

asMap in interface Multimap<K,V>

Specified by:

asMap in interface SetMultimap<K,V>

valueComparator

Comparator<? super V> valueComparator()

Returns the comparator that orders the multimap values, with null indicating that natural ordering is used.