edu.ucla.sspace.util

Interface MultiMap<K,V>

All Known Subinterfaces:

IntIntMultiMap, SortedMultiMap<K,V>

All Known Implementing Classes:

BoundedSortedMultiMap, HashMultiMap, IntIntHashMultiMap, TreeMultiMap

public interface MultiMap<K,V>

An object that maps a key to one or more values. A map cannot contain duplicate keys and each key cannot map to duplicate values.

See Also:

Map

Method Summary

Methods

Modifier and Type	Method and Description
Map<K,Set<V>>	asMap() Returns a Map-based view of this MultiMap
void	clear() Removes all of the mappings from this multi-map.
boolean	containsKey(Object key) Returns true if this multi-map contains a mapping for the specified key.
boolean	containsMapping(Object key, Object value) Returns true if this multi-map contains a mapping from specified key to the specified value.
boolean	containsValue(Object key) Returns true if this multi-map contains from any key to the specified value.
Set<Map.Entry<K,V>>	entrySet() Returns a Set view of all the key-value mappings contained in this multi-map.
Set<V>	get(Object key) Returns the set of values mapped to this key or null of the key is not mapped to any values
boolean	isEmpty() Returns true if this multi-map contains no mappings.
Set<K>	keySet() Returns a Set view of the mappings contained in this multi-map.
boolean	put(K key, V value) Adds the specified value to the set of values associated with the specified key in this map.
void	putAll(Map<? extends K,? extends V> m) Copies all of the mappings from the specified map to this mutli-map
void	putAll(MultiMap<? extends K,? extends V> m) Copies all of the mappings from the specified mulit-map to this mutli-map
boolean	putMany(K key, Collection<V> values) Adds all of the specified values to the set of values associated with the specified key in this map.
int	range() Returns the number of values maped to keys.
Set<V>	remove(K key) Removes the mapping for a key from this multi-map if it is present, returning any mapped values to that key
boolean	remove(Object key, Object value) Removes the specified mapping for a key if it is present.
int	size() Returns the number of keys that are mapped to one or more values in this multi-map.
Collection<V>	values() Returns a Collection view of the values contained in this map.
Collection<Set<V>>	valueSets() Returns a Collection view of the sets of values mapped to each key in this map.

Method Detail

asMap

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

Returns a Map-based view of this MultiMap

clear

void clear()

Removes all of the mappings from this multi-map.

containsKey

boolean containsKey(Object key)

Returns true if this multi-map contains a mapping for the specified key.

containsMapping

boolean containsMapping(Object key,
                      Object value)

Returns true if this multi-map contains a mapping from specified key to the specified value.

containsValue

boolean containsValue(Object key)

Returns true if this multi-map contains from any key to the specified value.

entrySet

Set<Map.Entry<K,V>> entrySet()

Returns a Set view of all the key-value mappings contained in this multi-map.

get

Set<V> get(Object key)

Returns the set of values mapped to this key or null of the key is not mapped to any values

isEmpty

boolean isEmpty()

Returns true if this multi-map contains no mappings.

keySet

Set<K> keySet()

Returns a Set view of the mappings contained in this multi-map.

put

boolean put(K key,
          V value)

Adds the specified value to the set of values associated with the specified key in this map.

Parameters:

key - key with which the specified value is to be associated

value - a value to be associated with the specified key

Returns:

true if the provided value was not already in the set of value mapped to the specified key

putAll

void putAll(Map<? extends K,? extends V> m)

Copies all of the mappings from the specified map to this mutli-map

putAll

void putAll(MultiMap<? extends K,? extends V> m)

Copies all of the mappings from the specified mulit-map to this mutli-map

putMany

boolean putMany(K key,
              Collection<V> values)

Adds all of the specified values to the set of values associated with the specified key in this map.

Parameters:

key - key with which the specified value is to be associated

values - a collection of values to be associated with the specified key

Returns:

true if at least one of the provided value was not already in the set of value mapped to the specified key

remove

Set<V> remove(K key)

Removes the mapping for a key from this multi-map if it is present, returning any mapped values to that key

Returns:

the set of values mapped to the key or the empty set if the key was not present

remove

boolean remove(Object key,
             Object value)

Removes the specified mapping for a key if it is present. If the key is mapped to other values, it is retained, otherwise the key is removed from the map. This method provides a way to remove a specific mapping for a key without removing all other existing mappings.

Returns:

true if the specified mapping was removed

range

int range()

Returns the number of values maped to keys. Note that in the bijective case, this will equal the value returned by size(). However, in the case where a key is mapped to more than one value, this method will always return a value strictly larger than size().

Returns:

the number of values maped to keys

size

int size()

Returns the number of keys that are mapped to one or more values in this multi-map.

See Also:

range()

values

Collection<V> values()

Returns a Collection view of the values contained in this map.

valueSets

Collection<Set<V>> valueSets()

Returns a Collection view of the sets of values mapped to each key in this map.