com.vignette.portal.cache
Class SoftLeastRecentlyUsedStrategy

java.lang.Object
  |
  +--com.vignette.portal.cache.CacheStrategy
        |
        +--com.vignette.portal.cache.ActionBasedCacheStrategy
              |
              +--com.vignette.portal.cache.SizeBasedStrategy
                    |
                    +--com.vignette.portal.cache.LeastRecentlyUsedStrategy
                          |
                          +--com.vignette.portal.cache.SoftLeastRecentlyUsedStrategy

All Implemented Interfaces:

Periodical

public class SoftLeastRecentlyUsedStrategy

extends LeastRecentlyUsedStrategy

implements Periodical

Periodically checks that the size threshold is not exceeded.

This strategy implements the Periodical interface and checks the size boundary as part of its SoftLeastRecentlyUsedStrategy.onPeriod(long) method. Between periods, the cache is allowed to grow in an unbounded fashion and gets trimmed at the following periodical check. Its overhead is lower that some of the more aggressive strategies, but it has a potential for overrunning the memory.

See Also:

HardLeastRecentlyUsedStrategy

Constructor Summary

SoftLeastRecentlyUsedStrategy(CacheAction action, int sizeOfCache)
Creates a cache of specified size with specified action logic.

SoftLeastRecentlyUsedStrategy(int sizeOfCache)
Creates a cache of specified size with default action logic.

Method Summary

void	onPeriod(long now)
void	onPut(Object key, Object value, Map properties) Someone wants to add the pair key / value to the cache.
void	onPutAll(Map keyValuePairs, Map properties) Someone wants to add the pairs in keyValuePairs to the cache.

Methods inherited from class com.vignette.portal.cache.LeastRecentlyUsedStrategy

onAdd, onAddAll, onGet, touch

Methods inherited from class com.vignette.portal.cache.SizeBasedStrategy

getSizeOfCache, onInvalidate, onInvalidateAll, onInvalidateAll, onRemove, onRemoveAll, onRemoveAll

Methods inherited from class com.vignette.portal.cache.ActionBasedCacheStrategy

getCacheAction, setStore

Methods inherited from class com.vignette.portal.cache.CacheStrategy

getStore, onGetAll

Methods inherited from class java.lang.Object

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

Constructor Detail

SoftLeastRecentlyUsedStrategy

public SoftLeastRecentlyUsedStrategy(int sizeOfCache)

Creates a cache of specified size with default action logic.

Parameters:

sizeOfCache - the maximum number of objects allowed in the cache.

See Also:

LeastRecentlyUsedStrategy.LeastRecentlyUsedStrategy(int)

SoftLeastRecentlyUsedStrategy

public SoftLeastRecentlyUsedStrategy(CacheAction action,
                                     int sizeOfCache)

Creates a cache of specified size with specified action logic.

Parameters:

action - the non-null action to invoke when the size of the cache is exceeded.

sizeOfCache - the maximum number of objects allowed in the cache.

See Also:

LeastRecentlyUsedStrategy.LeastRecentlyUsedStrategy(CacheAction, int)

Method Detail

onPut

public void onPut(Object key,
                  Object value,
                  Map properties)
           throws CacheException

Description copied from class: CacheStrategy

Someone wants to add the pair key / value to the cache. This strategy can reject the operation by throwing an exception. The actual addition, if allowed, will be signalled later by a call to this strategy's onAdd method.

Individual strategies can use the information in properties to override their creation-time parameters.

Overrides:

onPut in class CacheStrategy

Following copied from class: com.vignette.portal.cache.CacheStrategy

Parameters:

key - key being added

value - value being added, matching key

properties - possible overrides, can be null

onPutAll

public void onPutAll(Map keyValuePairs,
                     Map properties)
              throws CacheException

Description copied from class: CacheStrategy

Someone wants to add the pairs in keyValuePairs to the cache. This strategy can reject the operation by throwing an exception. The actual addition, if allowed, will be signalled later by a call to this strategy's onAddAll method.

Individual strategies can use the information in properties to override their creation-time parameters.

This is a default implementation. For performance purposes you may wish to override it. If you do, you should not be calling super.onPutAll(Map, Map).

Overrides:

onPutAll in class CacheStrategy

Following copied from class: com.vignette.portal.cache.CacheStrategy

Parameters:

keyValuePairs - key/value pairs being added

properties - possible overrides, can be null

onPeriod

public void onPeriod(long now)

Specified by:

onPeriod in interface Periodical