com.atlassian.confluence.impl.cache

Class ReadThroughEntityCache<CACHEKEY extends Serializable,ENTITYID extends Serializable,ENTITY>

java.lang.Object

com.atlassian.confluence.impl.cache.ReadThroughEntityCache<CACHEKEY,ENTITYID,ENTITY>

Type Parameters:

CACHEKEY - the cache key type. Must be Serializable.

ENTITYID - the entity ID type, used as the value in the cache. Must be Serializable.

ENTITY - the entity type, as will be returned from the get(Serializable, Supplier, Predicate) method

All Implemented Interfaces:

ReadThroughCache<CACHEKEY,ENTITY>

public final class ReadThroughEntityCache<CACHEKEY extends Serializable,ENTITYID extends Serializable,ENTITY>
extends Object
implements ReadThroughCache<CACHEKEY,ENTITY>

An implementation of ReadThroughCache which caches the IDs of entity objects against arbitrary keys. When fetched from the cache, the IDs will be deferenced back to the required entity objects before being returned.

Contains logic to handle cases where the cache contains a stale entity ID, i.e. where an entity for that ID no longer exists.

Since:

7.5

Constructor Summary

Constructors

Constructor and Description
ReadThroughEntityCache(ReadThroughCache<CACHEKEY,ENTITYID> backingCache, Function<ENTITYID,ENTITY> entityLoader, Function<ENTITY,ENTITYID> idExtractor)

Method Summary

Modifier and Type	Method and Description
static <E extends ConfluenceEntityObject,K extends Serializable> ReadThroughCache<K,E>	forConfluenceEntityObjects(ReadThroughCache<K,Long> cache, Function<Long,E> entityLoader) Creates a new ReadThroughCache for use with ConfluenceEntityObject entity types.
ENTITY	get(CACHEKEY cacheKey, Supplier<ENTITY> delegateLoader, Predicate<ENTITY> entityTester) Retrieve the value for the given key.
Map<CACHEKEY,ENTITY>	getBulk(Set<CACHEKEY> keys, Function<Set<CACHEKEY>,Map<CACHEKEY,ENTITY>> entityBulkLoader) Retrieves multiple values for the given keys.
void	remove(CACHEKEY cacheKey) Removs the cache entry for the given key.
void	removeAll() Removes all cache entries.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.atlassian.confluence.impl.cache.ReadThroughCache

get

Constructor Detail

ReadThroughEntityCache

public ReadThroughEntityCache(ReadThroughCache<CACHEKEY,ENTITYID> backingCache,
                              Function<ENTITYID,ENTITY> entityLoader,
                              Function<ENTITY,ENTITYID> idExtractor)

Parameters:

backingCache - The underlying ReadThroughCache to use.

entityLoader - The function for resolving an entity ID into an entity (e.g. a DAO method reference).

idExtractor - The function for extracting the ID from an entity.

Method Detail

forConfluenceEntityObjects

public static <E extends ConfluenceEntityObject,K extends Serializable> ReadThroughCache<K,E> forConfluenceEntityObjects(ReadThroughCache<K,Long> cache,
                                                                                                                         Function<Long,E> entityLoader)

Creates a new ReadThroughCache for use with ConfluenceEntityObject entity types. Uses the Long ID of the entity as the cached value.

Type Parameters:

E - The entity type (must be a subtype of ConfluenceEntityObject).

K - The type of the cache key (must be Serializable).

Parameters:

cache - The underlying ReadThroughCache to use.

entityLoader - The function for resolving an entity ID into an entity (e.g. a DAO method reference).

get

public ENTITY get(CACHEKEY cacheKey,
                  Supplier<ENTITY> delegateLoader,
                  Predicate<ENTITY> entityTester)

Retrieve the value for the given key. If the value is in the cache this will be returned, else the given delegate will be called to retrieve the value. If the delegate returns a value, and if it passes the given filter, it will be placed in the cache and returned. If the filter rejects the value, nothing will be placed in the cache but the value will be returned from the method.

Specified by:

get in interface ReadThroughCache<CACHEKEY extends Serializable,ENTITY>

Parameters:

cacheKey - the key to resolve in the cache

delegateLoader - A Supplier which will be called if there is no value in the cache (may return null).

entityTester - A Predicate that will be used to test the validity of any value in the cache or loaded from the supplier

Returns:

the cached value, or the value which was loaded from the supplier (may be null)

getBulk

public Map<CACHEKEY,ENTITY> getBulk(Set<CACHEKEY> keys,
                                    Function<Set<CACHEKEY>,Map<CACHEKEY,ENTITY>> entityBulkLoader)

Retrieves multiple values for the given keys. Any entries not already present in the cache will be supplied via the delegate loader.

Specified by:

getBulk in interface ReadThroughCache<CACHEKEY extends Serializable,ENTITY>

remove

public void remove(CACHEKEY cacheKey)

Description copied from interface: ReadThroughCache

Removs the cache entry for the given key.

Specified by:

remove in interface ReadThroughCache<CACHEKEY extends Serializable,ENTITY>

removeAll

public void removeAll()

Description copied from interface: ReadThroughCache

Removes all cache entries.

Specified by:

removeAll in interface ReadThroughCache<CACHEKEY extends Serializable,ENTITY>