Package org.jboss.weld.util.collections

Interface Multimap<K,V>

Type Parameters:

K - The key

V - The value

All Known Implementing Classes:

ListMultimap, SetMultimap

public interface Multimap<K,V>

A collection-like structure that maps keys to collections of values.

Author:

Martin Kouba

Method Summary

Modifier and Type	Method	Description
void	clear()	Removes all of the mappings.
boolean	containsKey(Object key)
Set<Map.Entry<K,Collection<V>>>	entrySet()	Map.Entry.getValue() always returns an unmodifiable collection.
Collection<V>	get(K key)	This method never returns null.
boolean	isEmpty()
Set<K>	keySet()
boolean	put(K key, V value)
boolean	putAll(K key, Collection<? extends V> values)
Collection<V>	replaceValues(K key, Iterable<? extends V> values)	Note that the original collection of values is completely replaced by a new collection which contains all elements from the given iterable.
int	size()	Unlike Guava'sMultimap#size() this method returns the number of key-value mappings.
Set<V>	uniqueValues()
List<V>	values()	The list may include the same value multiple times if it occurs in multiple mappings or if the collection of values for the mapping allows duplicate elements.

Method Detail

size

int size()

Unlike Guava'sMultimap#size() this method returns the number of key-value mappings.

Returns:

the number of key-value mappings

isEmpty

boolean isEmpty()

Returns:

true if there are no key-value mappings

get

Collection<V> get(K key)

This method never returns null. If no collection of values for a given key exists a new value collection is initialized.

Parameters:

key -

Returns:

the collection of values for the given key

put

boolean put(K key,
            V value)

Parameters:

key -

value -

Returns:

true if the the size of the collection associated with the given key increased, false otherwise (e.g. if the collection of values doesn't allow duplicates)

putAll

boolean putAll(K key,
               Collection<? extends V> values)

Parameters:

key -

values -

Returns:

true if the the size of the collection associated with the given key increased, false otherwise (e.g. if the collection of values doesn't allow duplicates)

replaceValues

Collection<V> replaceValues(K key,
                            Iterable<? extends V> values)

Note that the original collection of values is completely replaced by a new collection which contains all elements from the given iterable. If the collection of values doesn't allow duplicates, these elements are removed.

Parameters:

key -

values -

Returns:

the collection of replaced values

containsKey

boolean containsKey(Object key)

Parameters:

key -

Returns:

true if the multimap contains a mapping for the given key

keySet

Set<K> keySet()

Returns:

an immutable set of keys

values

List<V> values()

The list may include the same value multiple times if it occurs in multiple mappings or if the collection of values for the mapping allows duplicate elements.

Returns:

an immutable list of all the values in the multimap

uniqueValues

Set<V> uniqueValues()

Returns:

an immutable set of all the values in the multimap

entrySet

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

Map.Entry.getValue() always returns an unmodifiable collection. Map.Entry.setValue(Object) operation is not supported.

Returns:

an immutable set of all key-value pairs

clear

void clear()

Removes all of the mappings.