com.jidefx.utils

Class CacheMap<T,K>

java.lang.Object

com.jidefx.utils.CacheMap<T,K>

public class CacheMap<T,K>
extends java.lang.Object

CacheMap is a two-level HashMap. It uses Class as the key and you can map the key to an object and a context as a pair. We use context because we want to register multiple objects with the same Class. register(Class, Object, Object) is the method to register a new entry. getRegisteredObject(Class, Object) will allow you to look up the object by specifying the Class and the context.

Constructor Summary

Constructors

Constructor and Description
CacheMap(K defaultContext) Constructs a CacheMap.

Method Summary

Modifier and Type	Method and Description
void	clear()
protected com.jidefx.utils.CacheMap.Cache<K,T>	getCache(java.lang.Class<?> clazz)
K[]	getKeys(java.lang.Class<?> clazz, K[] a) Gets the secondary keys that are registered with the class in CacheMap.
T	getMatchRegisteredObject(java.lang.Class<?> clazz, K context) Gets the exact match registered object.
T	getRegisteredObject(java.lang.Class<?> clazz, K context) Gets registered object from CacheMap.
java.util.List<T>	getValues()
protected com.jidefx.utils.CacheMap.Cache<K,T>	initCache(java.lang.Class<?> clazz)
void	register(java.lang.Class<?> clazz, T object, K context) Registers an object with the specified clazz and object.
void	remove(java.lang.Class<?> clazz) Remove all registrations for the designated class.
void	unregister(java.lang.Class<?> clazz, K context) Unregisters the object associated with the specified class and context.

Methods inherited from class java.lang.Object

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

Constructor Detail

CacheMap

public CacheMap(K defaultContext)

Constructs a CacheMap.

Parameters:

defaultContext - the default context.

Method Detail

getCache

protected com.jidefx.utils.CacheMap.Cache<K,T> getCache(java.lang.Class<?> clazz)

getKeys

public K[] getKeys(java.lang.Class<?> clazz,
                   K[] a)

Gets the secondary keys that are registered with the class in CacheMap.

Parameters:

clazz - the class

a - the array to receive the keys.

Returns:

the secondary keys.

initCache

protected com.jidefx.utils.CacheMap.Cache<K,T> initCache(java.lang.Class<?> clazz)

register

public void register(java.lang.Class<?> clazz,
                     T object,
                     K context)

Registers an object with the specified clazz and object.

Parameters:

clazz - the class which is used as the key.

object - the object, or the value of the mapping

context - the secondary key. It is used to register multiple objects to the same primary key (the clazz parameter in this case).

unregister

public void unregister(java.lang.Class<?> clazz,
                       K context)

Unregisters the object associated with the specified class and context.

Parameters:

clazz - the class

context - the context

getRegisteredObject

public T getRegisteredObject(java.lang.Class<?> clazz,
                             K context)

Gets registered object from CacheMap. The algorithm used to look up is
1. First check for exact match with clazz and context.
2. If didn't find, look for interfaces that clazz implements using the exact context.
3. If still didn't find, look for super class of clazz using the exact context.
4. If still didn't find, using the exact clazz with default context.
5. If still didn't find, return null.
If found a match in step 1, 2, 3 or 4, it will return the registered object immediately.

Parameters:

clazz - the class which is used as the primary key.

context - the context which is used as the secondary key. This parameter could be null in which case the default context is used.

Returns:

registered object the object associated with the class and the context.

getMatchRegisteredObject

public T getMatchRegisteredObject(java.lang.Class<?> clazz,
                                  K context)

Gets the exact match registered object. Different from getRegisteredObject(Class, Object) which will try different context and super classes and interfaces to find match. This method will do an exact match.

Parameters:

clazz - the class which is used as the primary key.

context - the context which is used as the secondary key. This parameter could be null in which case the default context is used.

Returns:

registered object the object associated with the class and the context.

getValues

public java.util.List<T> getValues()

remove

public void remove(java.lang.Class<?> clazz)

Remove all registrations for the designated class.

Parameters:

clazz - the class

clear

public void clear()