net.sf.ehcache.extension
Interface CacheExtension

public interface CacheExtension

This is a general purpose mechanism to allow generic extensions to a Cache.

CacheExtensions are tied into the Cache lifecycle. For that reason this interface has the lifecycle methods.

CacheExtensions are created using the CacheExtensionFactory which has a createCacheCacheExtension() method which takes as a parameter a Cache and properties. It can thus call back into any public method on Cache, including, of course, the load methods.

CacheExtensions are suitable for timing services, where you want to create a timer to perform cache operations. The other way of adding Cache behaviour is to decorate a cache. See BlockingCache for an example of how to do this.

Because a CacheExtension holds a reference to a Cache, the CacheExtension can do things such as registering a CacheEventListener or even a CacheManagerEventListener, all from within a CacheExtension, creating more opportunities for customisation.

Version:

$Id: CacheExtension.java 535 2007-08-12 01:32:14Z gregluck $

Author:

Greg Luck

Method Summary

CacheExtension	clone(Ehcache cache) Creates a clone of this extension.
void	dispose() Providers may be doing all sorts of exotic things and need to be able to clean up on dispose.
Status	getStatus()
void	init() Notifies providers to initialise themselves.

Method Detail

init

void init()

Notifies providers to initialise themselves.

This method is called during the Cache's initialise method after it has changed it's status to alive. Cache operations are legal in this method.

Throws:

CacheException

dispose

void dispose()
             throws CacheException

Providers may be doing all sorts of exotic things and need to be able to clean up on dispose.

Cache operations are illegal when this method is called. The cache itself is partly disposed when this method is called.

Throws:

CacheException

clone

CacheExtension clone(Ehcache cache)
                     throws java.lang.CloneNotSupportedException

Creates a clone of this extension. This method will only be called by ehcache before a cache is initialized.

Implementations should throw CloneNotSupportedException if they do not support clone but that will stop them from being used with defaultCache.

Returns:

a clone

Throws:

java.lang.CloneNotSupportedException - if the extension could not be cloned.

getStatus

Status getStatus()

Returns:

the status of the extension