org.axonframework.cache

Interface Cache

All Known Implementing Classes:

AbstractCacheAdapter, EhCacheAdapter, JCacheAdapter, NoCache, WeakReferenceCache

public interface Cache

Abstraction for a Caching mechanism. All Axon component rely on this abstraction, so that different providers can be plugged in. In future versions, this abstraction may be replaced with the javax.cache api, as soon as that api is final.

Since:

2.1.2

Author:

Allard Buijze

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Cache.EntryListener Interface describing callback methods, which are invoked when changes are made in the underlying cache.
static class	Cache.EntryListenerAdapter Adapter implementation for the EntryListener, allowing for overriding only specific callback methods.

Method Summary

Methods

Modifier and Type	Method and Description
<K> boolean	containsKey(K key) Indicates whether there is an item stored under given key.
<K,V> V	get(K key) Returns an item from the cache, or null if no item was stored under that key
<K,V> void	put(K key, V value) Stores the given value in the cache, under given key.
<K,V> boolean	putIfAbsent(K key, V value) Stores the given value in the cache, under given key, if no element is yet available under that key.
void	registerCacheEntryListener(Cache.EntryListener cacheEntryListener) Registers the given cacheEntryListener to listen for Cache changes.
<K> boolean	remove(K key) Removes the entry stored under given key.
void	unregisterCacheEntryListener(Cache.EntryListener cacheEntryListener) Unregisters the previously registered cacheEntryListener.

Method Detail

get

<K,V> V get(K key)

Returns an item from the cache, or null if no item was stored under that key

Type Parameters:

K - The type of key used

V - The type of value stored

Parameters:

key - The key under which the item was cached

Returns:

the item stored under the given key

put

<K,V> void put(K key,
             V value)

Stores the given value in the cache, under given key. If an item already exists, it is updated with the new value.

Type Parameters:

K - The type of key used

V - The type of value stored

Parameters:

key - The key under which to store the item

value - The item to cache

putIfAbsent

<K,V> boolean putIfAbsent(K key,
                        V value)

Stores the given value in the cache, under given key, if no element is yet available under that key. This operation is performed atomically.

Type Parameters:

K - The type of key used

V - The type of value stored

Parameters:

key - The key under which to store the item

value - The item to cache

Returns:

true if no value was previously assigned to the key, false otherwise.

remove

<K> boolean remove(K key)

Removes the entry stored under given key. If no such entry exists, nothing happens.

Type Parameters:

K - The type of key used

Parameters:

key - The key under which the item was stored

Returns:

true if a value was previously assigned to the key and has been removed, false otherwise.

containsKey

<K> boolean containsKey(K key)

Indicates whether there is an item stored under given key.

Type Parameters:

K - The type of key

Parameters:

key - The key to check

Returns:

true if an item is available under that key, false otherwise.

registerCacheEntryListener

void registerCacheEntryListener(Cache.EntryListener cacheEntryListener)

Registers the given cacheEntryListener to listen for Cache changes.

Parameters:

cacheEntryListener - The listener to register

unregisterCacheEntryListener

void unregisterCacheEntryListener(Cache.EntryListener cacheEntryListener)

Unregisters the previously registered cacheEntryListener.

Parameters:

cacheEntryListener - The listener to unregister