org.jcreme.caches
Class CompositeCache

java.lang.Object
  org.jcreme.caches.BaseCache
      org.jcreme.caches.CompositeCache

All Implemented Interfaces:

Cache

public class CompositeCache

extends BaseCache

This class models a Cache that is based on subcaches. All the Caches are used. There is an order of priority between the sub caches so that the results coming from one have preeminence over the next ones. The highest priority cache is used when objects are registered in this cache.

Version:

$Revision: 1.3 $

Author:

$Author: dbregeon $

Constructor Summary

CompositeCache(Cache mainSubCache)
Creates a new instance of CompositeCache

CompositeCache(Cache[] subCaches)
Creates a new instance of CompositeCache.

Method Summary

void	addSubCache(Cache cache) Adds a cache at the end of the list of Cache.
void	clear() Removes all the objects from the Cache, leaving it empty.
java.lang.Object[]	getAllObjects() This method gives access to the full content of the cache.
java.lang.Object[]	getAllObjects(java.lang.Class type) This method gives the same result as the getAllObjects method but the objects in the result array are types with the parameter type.
java.util.Map	getMap() This method enables to access to the cache contents.
java.lang.Object	getObject(java.lang.Object key) Gives access to an object registered in the cache.
int	getSize() This methods gives the current size of the cache.
void	insertSubCache(Cache cache, int position) Adds a cache at the given position of the list of Cache.
void	registerAllObjects(java.util.Map m) This is a convenience method.
void	registerObject(java.lang.Object key, java.lang.Object value) Registers an object in the cache using the given key to refer to it.
void	removeSubCache(Cache cache) Removes a cache from the list.
void	removeSubCache(int position) Removes a cache from the list.
void	unregisterObject(java.lang.Object key) Removes the object associated with the given key from the Cache.

Methods inherited from class org.jcreme.caches.BaseCache

addCacheListener, buildEvent, fireElementAdded, fireElementRemoved, getCacheListeners, getMaxSize, getMinSize, getReplacementPolicy, removeCacheListener, setMaxSize, setReplacementPolicy

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeCache

public CompositeCache(Cache mainSubCache)
               throws java.lang.IllegalArgumentException

Creates a new instance of CompositeCache

Parameters:

mainSubCache - the main cache in the composite. It is the cache that is primarily used to register objects.

Throws:

java.lang.IllegalArgumentException - if the mainSubCache is null.

CompositeCache

public CompositeCache(Cache[] subCaches)
               throws java.lang.IllegalArgumentException

Creates a new instance of CompositeCache.

Parameters:

subCaches - the subcaches to use. The first cache in the array will be considered the main cache.

Throws:

java.lang.IllegalArgumentException - if the subCaches is null or empty.

Method Detail

clear

public void clear()

Removes all the objects from the Cache, leaving it empty.

Specified by:

clear in interface Cache

Specified by:

clear in class BaseCache

getAllObjects

public java.lang.Object[] getAllObjects()

This method gives access to the full content of the cache.

Specified by:

getAllObjects in interface Cache

Specified by:

getAllObjects in class BaseCache

Returns:

an array containing all the objects stored in the cache.

getAllObjects

public java.lang.Object[] getAllObjects(java.lang.Class type)

This method gives the same result as the getAllObjects method but the objects in the result array are types with the parameter type.

Specified by:

getAllObjects in interface Cache

Specified by:

getAllObjects in class BaseCache

Parameters:

type - the type to give to the object in the result array.

Returns:

an array of objects of the type.

getMap

public java.util.Map getMap()

This method enables to access to the cache contents.

Returns:

a map of the (key,value) contents of the cache.

getObject

public java.lang.Object getObject(java.lang.Object key)

Gives access to an object registered in the cache.

Specified by:

getObject in interface Cache

Specified by:

getObject in class BaseCache

Parameters:

key - the key used to register the searched object.

Returns:

the object stored in the cache. Null if no object was stored with this key.

getSize

public int getSize()

This methods gives the current size of the cache.

Specified by:

getSize in interface Cache

Specified by:

getSize in class BaseCache

Returns:

the number of objects currently stored in the cache.

registerAllObjects

public void registerAllObjects(java.util.Map m)
                        throws CacheFullException

This is a convenience method. It enables to add to the cache all the objects present in the map.

Parameters:

m - the map that contains the objects (and keys) to use.

Throws:

CacheFullException - when the Cache would exceed its maximum size and no room can be made.

registerObject

public void registerObject(java.lang.Object key,
                           java.lang.Object value)
                    throws CacheFullException

Registers an object in the cache using the given key to refer to it.

Specified by:

registerObject in interface Cache

Specified by:

registerObject in class BaseCache

Parameters:

key - the key to use to retrieve the object.

value - the object to store in the Cache.

Throws:

CacheFullException - when the Cache would exceed its maximum size and no room can be made.

unregisterObject

public void unregisterObject(java.lang.Object key)

Removes the object associated with the given key from the Cache.

Specified by:

unregisterObject in interface Cache

Specified by:

unregisterObject in class BaseCache

Parameters:

key - the key associated to the object to be removed.

addSubCache

public void addSubCache(Cache cache)

Adds a cache at the end of the list of Cache.

Parameters:

cache - the cache to be added. Nothing happens it it is null or if it already is in the CompositeCache.

insertSubCache

public void insertSubCache(Cache cache,
                           int position)

Adds a cache at the given position of the list of Cache.

Parameters:

cache - the cache to be added. Nothing happens it it is null or if it already is in the CompositeCache.

position - in the CompositeCache. If the position is lesser than -1 or greater than the number of caches in the composite, the cache is added at the last position.

removeSubCache

public void removeSubCache(Cache cache)

Removes a cache from the list.

Parameters:

cache - the cache to be removed. Nothing happens it it is null or if it already is in the CompositeCache.

removeSubCache

public void removeSubCache(int position)

Removes a cache from the list.

Parameters:

position - the position of the cache to remove.