LRUCachePolicy

Overview

Package

Class

Tree

Deprecated

Index

Help

PREV CLASS (src) NEXT CLASS (src)

FRAMES NO FRAMES

SUMMARY: NESTED | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

org.jboss.util
Class LRUCachePolicy

java.lang.Object
  org.jboss.util.LRUCachePolicy

All Implemented Interfaces:: CachePolicy (src)

Direct Known Subclasses:: LRUEnterpriseContextCachePolicy (src) , LRUPool (src) , LRUPool (src) , PreparedStatementCache (src)

public class LRUCachePolicy
extends java.lang.Object
implements CachePolicy (src)

Implementation of a Least Recently Used cache policy.

Nested Class Summary
`class`	`LRUCachePolicy.LRUCacheEntry (src)` Double linked cell used as entry in the cache list.
`class`	`LRUCachePolicy.LRUList (src)` Double queued list used to store cache entries.

Field Summary
`protected LRUCachePolicy.LRUList (src)`	`m_list` The linked list used to implement the LRU algorithm
`protected java.util.HashMap`	`m_map` The map holding the cached objects
`protected int`	`m_maxCapacity` The maximum capacity of this cache
`protected int`	`m_minCapacity` The minimum capacity of this cache

Constructor Summary
`LRUCachePolicy()` Creates a LRU cache policy object with zero cache capacity.
`LRUCachePolicy(int min, int max)` Creates a LRU cache policy object with the specified minimum and maximum capacity.

Method Summary
`protected void`	`ageOut(LRUCachePolicy.LRUCacheEntry (src) entry)` Callback method called when the cache algorithm ages out of the cache the given entry.
`protected void`	`cacheMiss()` Callback method called when a cache miss happens.
`void`	`create()` Initializes the cache, creating all required objects and initializing their values.
`protected LRUCachePolicy.LRUCacheEntry (src)`	`createCacheEntry(java.lang.Object key, java.lang.Object value)` Factory method for cache entries
`protected LRUCachePolicy.LRUList (src)`	`createList()` Factory method for the linked list used by this cache implementation.
`void`	`destroy()` Destroys the cache that is now unusable.
`void`	`flush()` Flushes the cached objects from the cache.
`java.lang.Object`	`get(java.lang.Object key)` Returns the object paired with the specified key if it's present in the cache, otherwise must return null.
`void`	`insert(java.lang.Object key, java.lang.Object o)` Inserts the specified object into the cache following the implemented policy.
`java.lang.Object`	`peek(java.lang.Object key)` Returns the object paired with the specified key if it's present in the cache, otherwise must return null.
`void`	`remove(java.lang.Object key)` Remove the cached object paired with the specified key.
`int`	`size()` Get the size of the cache.
`void`	`start()` Starts this cache that is now ready to be used.
`void`	`stop()` Stops this cache thus `flush()`ing all cached objects.

Methods inherited from class java.lang.Object

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

Field Detail

m_map

protected java.util.HashMap m_map

The map holding the cached objects

m_list

protected LRUCachePolicy.LRUList (src)  m_list

The linked list used to implement the LRU algorithm

m_maxCapacity

protected int m_maxCapacity

The maximum capacity of this cache

m_minCapacity

protected int m_minCapacity

The minimum capacity of this cache

Constructor Detail

LRUCachePolicy

public LRUCachePolicy()

Creates a LRU cache policy object with zero cache capacity.
See Also:: create()

LRUCachePolicy

public LRUCachePolicy(int min,
                      int max)

Creates a LRU cache policy object with the specified minimum and maximum capacity.
See Also:: create()

Method Detail

create

public void create()

Initializes the cache, creating all required objects and initializing their values.

Specified by:: create in interface CachePolicy (src)

See Also:: start(), destroy()

start

public void start()

Starts this cache that is now ready to be used.

Specified by:: start in interface CachePolicy (src)

See Also:: create(), stop()

stop

public void stop()

Stops this cache thus flush()ing all cached objects.
After this method is called, a call to start() will restart the cache.

Specified by:: stop in interface CachePolicy (src)

See Also:: start(), destroy()

destroy

public void destroy()

Destroys the cache that is now unusable.
To have it working again it must be re-create()ed and re-start()ed.

Specified by:: destroy in interface CachePolicy (src)

See Also:: create()