org.tinygroup.jspengine.appserv.util.cache

Interface Cache

All Known Implementing Classes:

BaseCache, BoundedMultiLruCache, LruCache, MultiLruCache

public interface Cache

Cache Generic cache interface

Method Summary

Modifier and Type	Method and Description
void	add(Object key, Object value) add the given value to the cache at the specified key
void	add(Object key, Object value, int size) add the given value with specified size to the cache at specified key
void	addCacheListener(CacheListener listener) add the cache module listener
int	clear() clear all the entries from the cache.
void	clearStats() clear all stats
boolean	contains(Object key) check if the cache contains the item at the key
void	destroy() Destroys this cache.
Enumeration	elements() get an Enumeration for the keys stored in the cache
Object	get(Object key) get the item stored at the key.
Iterator	getAll(Object key) get all the items with the given key.
int	getEntryCount() get the number of entries in the cache
int	getIndex(Object key) get the index of the item given a key
Object	getStatByName(String key) get the desired statistic counter
Map	getStats() get the stats snapshot
void	init(int maxEntries, float loadFactor, Properties props) initialize the cache
void	init(int maxEntries, Properties props) initialize the cache with the default load factor (0.75)
boolean	isEmpty() is this cache empty?
Iterator	keys() get an Iterator for the keys stored in the cache
void	notifyRefresh(int index) notify threads waiting for a refresh on the object associated with the key
Object	put(Object key, Object value) cache the given value at the specified key and return previous value
Object	put(Object key, Object value, int size) cache the given value at the specified key and return previous value
Object	remove(Object key) remove the item with the given key.
Object	remove(Object key, Object value) remove the given value stored at the key.
void	removeAll(Object key) remove all the item with the given key.
void	trimExpiredEntries(int maxCount) trim the expired entries from the cache.
Iterator	values() get an Iterator for the values stored in the cache
boolean	waitRefresh(int index) wait for a refresh on the object associated with the key

Method Detail

init

void init(int maxEntries,
          float loadFactor,
          Properties props)
   throws Exception

initialize the cache

Parameters:

maxEntries - maximum number of entries expected in the cache

loadFactor - the load factor

props - opaque list of properties for a given cache implementation

Throws:

a - generic Exception if the initialization failed

Exception

init

void init(int maxEntries,
          Properties props)
   throws Exception

initialize the cache with the default load factor (0.75)

Parameters:

maxEntries - maximum number of entries expected in the cache

props - opaque list of properties for a given cache implementation

Throws:

a - generic Exception if the initialization failed

Exception

addCacheListener

void addCacheListener(CacheListener listener)

add the cache module listener

Parameters:

listener - CacheListener implementation

getIndex

int getIndex(Object key)

get the index of the item given a key

Parameters:

key - of the entry

Returns:

the index to be used in the cache

get

Object get(Object key)

get the item stored at the key.

Parameters:

key - lookup key

getAll

Iterator getAll(Object key)

get all the items with the given key.

Parameters:

key - lookup key

contains

boolean contains(Object key)

check if the cache contains the item at the key

Parameters:

key - lookup key

keys

Iterator keys()

get an Iterator for the keys stored in the cache

elements

Enumeration elements()

get an Enumeration for the keys stored in the cache

values

Iterator values()

get an Iterator for the values stored in the cache

put

Object put(Object key,
           Object value)

cache the given value at the specified key and return previous value

Parameters:

key - lookup key

object - item value to be stored

put

Object put(Object key,
           Object value,
           int size)

cache the given value at the specified key and return previous value

Parameters:

key - lookup key

object - item value to be stored

size - in bytes of the value being cached

add

void add(Object key,
         Object value)

add the given value to the cache at the specified key

Parameters:

key - lookup key

object - item value to be stored

This function is suitable for multi-valued keys.

add

void add(Object key,
         Object value,
         int size)

add the given value with specified size to the cache at specified key

Parameters:

key - lookup key

object - item value to be stored

size - in bytes of the value being added

This function is suitable for multi-valued keys.

remove

Object remove(Object key)

remove the item with the given key.

Parameters:

key - lookup key

remove

Object remove(Object key,
              Object value)

remove the given value stored at the key.

Parameters:

key - lookup key

value - to match (for multi-valued keys)

removeAll

void removeAll(Object key)

remove all the item with the given key.

Parameters:

key - lookup key

waitRefresh

boolean waitRefresh(int index)

wait for a refresh on the object associated with the key

Parameters:

index - index of the entry. The index must be obtained via one of the getIndex() methods.

notifyRefresh

void notifyRefresh(int index)

notify threads waiting for a refresh on the object associated with the key

Parameters:

index - index of the entry. The index must be obtained via one of the getIndex() methods.

clear

int clear()

clear all the entries from the cache.

isEmpty

boolean isEmpty()

is this cache empty?

getEntryCount

int getEntryCount()

get the number of entries in the cache

Returns:

the number of entries the cache currently holds

getStatByName

Object getStatByName(String key)

get the desired statistic counter

Parameters:

key - to corresponding stat

Returns:

an Object corresponding to the stat See also: Constant.java for the key

getStats

Map getStats()

get the stats snapshot

Returns:

a Map of stats See also: Constant.java for the keys

clearStats

void clearStats()

clear all stats

trimExpiredEntries

void trimExpiredEntries(int maxCount)

trim the expired entries from the cache.

Parameters:

maxCount - maximum number of invalid entries to trim specify Integer.MAX_VALUE to trim all timedout entries

This call is to be scheduled by a thread managed by the container.

destroy

void destroy()

Destroys this cache. This method should perform final clean ups.