org.jcreme.caches
Class CachePolicy

java.lang.Object
  org.jcreme.enumerations.Enumeration
      org.jcreme.caches.CachePolicy

All Implemented Interfaces:

java.lang.Comparable, java.io.Serializable

public class CachePolicy

extends Enumeration

This Enumeration subclass describes the possible policies to manage the cache contents. Each member is a cache factory to be used by AggregateCache instances. Current implemented values are: NONE (this gives a HashCache): replacement is undefined. FIFO (this gives a FIFOCache): new elements push older ones. The oldest is removed. LUFO (this gives a LUFOCache): keep statistics on cache element usage. The least used element is removed. The policy choice for a cache depends heavily on the use of that cache.

Version:

$Revision: 1.3 $

Author:

$Author: dbregeon $

See Also:

Serialized Form

Field Summary

static CachePolicy	FIFO The 'FIFO' enumeration value.
static CachePolicy	LUFO The 'LUFO' enumeration value.
static CachePolicy	NONE The 'NONE' enumeration value.
static java.lang.String	S_FIFO The name for the 'FIFO' enumeration value.
static java.lang.String	S_LUFO The name for the 'LUFO' enumeration value.
static java.lang.String	S_NONE The name for the 'NONE' enumeration value.
(package private) static long	serialVersionUID

Constructor Summary

protected

CachePolicy(java.lang.String name) Creates new CachePolicy

Method Summary

static CachePolicy	get(java.lang.String name) This method retrieves a CachePolicy instance from its name.
BaseCache	getCacheInstance() This method provides a new cache that implements the policy.
BaseCache	getCacheInstance(int minSize, int maxSize) This method provides a new cache that implements the policy.
static CachePolicy[]	getCachePolicies() This methods gives the instances of this class.
protected java.util.Hashtable	getFromName() This method is for internal use only.
static Enumeration[]	getValues() This method enables to retrieve all the possible values of an Enumeration class.

Methods inherited from class org.jcreme.enumerations.Enumeration

compareTo, getName, readResolve, toString

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

S_FIFO

public static final java.lang.String S_FIFO

The name for the 'FIFO' enumeration value.

See Also:

Constant Field Values

FIFO

public static final CachePolicy FIFO

The 'FIFO' enumeration value.

S_LUFO

public static final java.lang.String S_LUFO

The name for the 'LUFO' enumeration value.

See Also:

Constant Field Values

LUFO

public static final CachePolicy LUFO

The 'LUFO' enumeration value.

S_NONE

public static final java.lang.String S_NONE

The name for the 'NONE' enumeration value.

See Also:

Constant Field Values

NONE

public static final CachePolicy NONE

The 'NONE' enumeration value.

Constructor Detail

CachePolicy

protected CachePolicy(java.lang.String name)

Creates new CachePolicy

Parameters:

name - the name of this enumerated value. It cannot be null.

Throws:

InvalidParameterException - if one of the parameters is null.

Method Detail

getFromName

protected java.util.Hashtable getFromName()

This method is for internal use only.

Specified by:

getFromName in class Enumeration

Returns:

the Hashtable that links the enumerated values names with the actual enumerated value.

get

public static CachePolicy get(java.lang.String name)

This method retrieves a CachePolicy instance from its name.

Parameters:

name - the name of the CachePolicy instance.

Returns:

the CachePolicy that has this name. Null if no value corresponding to this name was found.

getCachePolicies

public static CachePolicy[] getCachePolicies()

This methods gives the instances of this class.

Returns:

all the instances of this class.

getCacheInstance

public BaseCache getCacheInstance(int minSize,
                                  int maxSize)

This method provides a new cache that implements the policy.

Parameters:

minSize - the initial size of the cache.

maxSize - the maximum size of the created cache.

Returns:

a new cache that implements the policy.

getCacheInstance

public BaseCache getCacheInstance()

This method provides a new cache that implements the policy.

Returns:

a new cache that implements the policy.

getValues

public static Enumeration[] getValues()

This method enables to retrieve all the possible values of an Enumeration class.

Returns:

the values for this class.