velosurf.cache
Class Cache

java.lang.Object
  |
  +--velosurf.cache.Cache

public class Cache

extends java.lang.Object

Cache that keeps fetched instances in memory.

Three modes :

• NO_CACHE (cache='none', the default, in velosurf.xml) : no caching occurs on this entity.
• SOFT_CACHE (cache='soft' in velosurf.xml) : caching occurs as long as memory is ont reclaimed (see the behaviour of java soft references).
• FULL_CACHE (cache='full' in velosuf.xml) : caching occurs until manually freed.

For an entity's instances to be cached, the associated table must have a primary key (even if multivalued).

This caching mechanism is meant for straightforward optimizations in simple situations, for instance to avoid re-fetching the loggued user at each request. Please keep in mind that the cache can quickly become inconsistant if used in conjunction with complex modification queries (that occur in its back...).

Author:

Claude Brisson

Inner Class Summary

static class

Cache.ArrayKey

Field Summary

static int	FULL_CACHE constant used to specify the "full cache" mode
protected int	mCachingMethod The caching method this cache uses
protected java.util.Map	mInnerCache the inner map that stores associations
static int	NO_CACHE constant used to specify the "no cache" mode
static int	SOFT_CACHE constant used to specify the "soft cache" mode

Constructor Summary

Cache(int inCachingMethod)
Cache constructor

Method Summary

void	clear() Clear the cache
java.lang.Object	get(java.lang.Object inKey) Try to get an instance from the cache
void	put(java.lang.Object inKey, java.lang.Object inValue) Put an instance in the cache
int	size() Getter for the size of the cache

Methods inherited from class java.lang.Object

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

Field Detail

NO_CACHE

public static final int NO_CACHE

constant used to specify the "no cache" mode

SOFT_CACHE

public static final int SOFT_CACHE

constant used to specify the "soft cache" mode

FULL_CACHE

public static final int FULL_CACHE

constant used to specify the "full cache" mode

mCachingMethod

protected int mCachingMethod

The caching method this cache uses

mInnerCache

protected java.util.Map mInnerCache

the inner map that stores associations

Constructor Detail

Cache

public Cache(int inCachingMethod)

Cache constructor

Parameters:

inCachingMethod - required caching mode

Method Detail

put

public void put(java.lang.Object inKey,
                java.lang.Object inValue)

Put an instance in the cache

Parameters:

inKey - key field(s) of this instance

inValue - instance

size

public int size()

Getter for the size of the cache

Returns:

the size of the cache

get

public java.lang.Object get(java.lang.Object inKey)

Try to get an instance from the cache

Parameters:

inKey - key field(s) of the asked instance

Returns:

Asked instance or null if not found

clear

public void clear()

Clear the cache