io.neba.core.util

Class ConcurrentDistinctMultiValueMap<K,V>

java.lang.Object

io.neba.core.util.ConcurrentDistinctMultiValueMap<K,V>

Type Parameters:

K - The key's type.

V - The value's type.

public class ConcurrentDistinctMultiValueMap<K,V>
extends Object

A thread-safe storage for key -> value associations. Note that it is not save to modify the contents of the collection returned by this map since it is still based on the contents of this map and not a shallow copy for performance considerations.
In addition, the values stored in this map are distinct, i.e. if a value already exists in the values collection it is removed prior to the insertion of the new element.

Author:

Olaf Otto

See Also:

ConcurrentLinkedDistinctQueue

Constructor Summary

Constructors

Constructor and Description
ConcurrentDistinctMultiValueMap()

Method Summary

Modifier and Type	Method and Description
void	clear()
Collection<V>	computeIfAbsent(K key, Function<? super K,? extends Collection<V>> mappingFunction)
Collection<V>	get(K key)
boolean	isEmpty()
void	put(K key, Collection<V> values)
void	put(K key, V value)
Collection<V>	remove(K key)
void	removeValue(V value) Removes the given value from all collections stored under any key.
Map<K,Collection<V>>	shallowCopy()
int	size()
Collection<Collection<V>>	values()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ConcurrentDistinctMultiValueMap

public ConcurrentDistinctMultiValueMap()

Method Detail

get

public Collection<V> get(K key)

put

public void put(K key,
                V value)

clear

public void clear()

remove

public Collection<V> remove(K key)

values

public Collection<Collection<V>> values()

put

public void put(K key,
                Collection<V> values)

computeIfAbsent

public Collection<V> computeIfAbsent(K key,
                                     Function<? super K,? extends Collection<V>> mappingFunction)

Parameters:

key - must not be null.

mappingFunction - must not be null.

Returns:

the existing value, or the value computed by the mapping function, which may be null.

shallowCopy

public Map<K,Collection<V>> shallowCopy()

Returns:

a shallow copy of the current state of this map. Note that the map values (the collection) are also copied; it is thus save to modify the state of the returned map and the state of the collections returned as the map values. Never returns null.

size

public int size()

isEmpty

public boolean isEmpty()

removeValue

public void removeValue(V value)

Removes the given value from all collections stored under any key.

Parameters:

value - must not be null.