com.atlassian.jira.util

Interface CacheMap<K,V>

public interface CacheMap<K,V>

An object that caches values that are mapped under keys. A CacheMap cannot contain duplicate keys; each key can map to at most one value.

The cache looks a lot like a Map and indeed implementations are likely to use a Map interally as the data store, however not all operations are implemented or exactly the same so this interface does not extend Map.

Since:

v4.0

Method Summary

Modifier and Type	Method and Description
void	clear() Removes all of the mappings from this cache.
Collection<V>	copyOfValues() Returns a Collection view of the values contained in this cache.
V	get(K key) Returns the value to which the specified key is mapped, or null if this cache contains no mapping for the key.
void	put(K key, V value) Maps the specified key to the specified value in this cache.
void	remove(K key) Removes the key (and its corresponding value) from this cache.

Method Detail

get

V get(K key)

Returns the value to which the specified key is mapped, or null if this cache contains no mapping for the key.

Parameters:

key - the key.

Returns:

the value to which the specified key is mapped.

put

void put(K key,
         V value)

Maps the specified key to the specified value in this cache.

The value can be retrieved by calling the get method with a key that is equal to the original key.

Parameters:

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

value - value to be associated with the specified key

clear

void clear()

Removes all of the mappings from this cache.

remove

void remove(K key)

Removes the key (and its corresponding value) from this cache. This method does nothing if the key is not in the cache.

Parameters:

key - the key that needs to be removed

copyOfValues

Collection<V> copyOfValues()

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

The collection is a copy of the values that were contained at the time that this operation was called. Concurrent implementations of this interface will likely allow mutating operations to occur while the collection is being constructed, and which of these modifications are in the resulting collection will be timing and implementation dependant.

Returns:

a Collection view of the values contained in this cache.