Package org.hippoecm.hst.cache

Interface HstCache

public interface HstCache

HST Cache Interface for cache related activities. Abstraction around physical cache implementation.

Version:

$Id$

Method Summary

Modifier and Type	Method	Description
void	clear()
CacheElement	createElement(Object key, Object content)
CacheElement	createUncacheableElement(Object key, Object content)
CacheElement	get(Object key)	Returns the CacheElement for key and null otherwise.
CacheElement	get(Object key, Callable<? extends CacheElement> valueLoader)	Returns cached object associated with the key in the cache, obtaining that value from the valueLoader if necessary.
int	getMaxSize()
int	getSize()
int	getTimeToIdleSeconds()
int	getTimeToLiveSeconds()
boolean	isKeyInCache(Object key)
void	put(CacheElement object)
boolean	remove(Object key)

Method Details

createElement

CacheElement createElement(Object key,
 Object content)

createUncacheableElement

CacheElement createUncacheableElement(Object key,
 Object content)

Returns:

a CacheElement that is marked to be uncacheable

put

void put(CacheElement object)

get

CacheElement get(Object key)

Returns the CacheElement for key and null otherwise.

Parameters:

key -

Returns:

the CacheElement for key and null otherwise

get

CacheElement get(Object key,
 Callable<? extends CacheElement> valueLoader)
          throws Exception

Returns cached object associated with the key in the cache, obtaining that value from the valueLoader if necessary. It provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern. The entire method invocation is performed atomically and the function is called at most once per key. Concurrent requests with the same key are blocked until the value is obtained from the function.

Parameters:

key - the key to get from the cache or to put an object for in the cache when the cache does not yet contain key

valueLoader - will be used to load the value for key if cache does not yet contain an object for key. The loaded value is put in the cache. The valueLoader is not allowed to return null but is allowed to return a CacheElement with content null.

Returns:

the element from the cache, or the just retrieved and stored element through valueloader

Throws:

Exception

isKeyInCache

boolean isKeyInCache(Object key)

remove

boolean remove(Object key)

clear

void clear()

getTimeToIdleSeconds

int getTimeToIdleSeconds()

getTimeToLiveSeconds

int getTimeToLiveSeconds()

getSize

int getSize()

getMaxSize

int getMaxSize()