org.norther.tammi.core.cache
Interface Cache<K,V>

Type Parameters:

K - the type of keys maintained by the cache.

V - the type of cached values.

All Superinterfaces:

CachedMap<K,V>, ConcurrentMap<K,V>, Map<K,V>

All Known Subinterfaces:

ResourceCache, SessionManager, SharedCache<K,V>

All Known Implementing Classes:

DefaultCache, DefaultResourceCache, DefaultSessionManager, DefaultSharedCache

public interface Cache<K,V>
extends CachedMap<K,V>

Extends CachedMap to adapt a cache supporting expiration of old entries. The map has a default expiration time, which is used for objects put into the map without an explicit expiration frequency. The maximum expiration time specifies the longest possible expiration time for the map. Its value may affect the performance of the map and should be realistic. Expired entries are searched at regular intervals specified by the expiration sleep interval. All times are given in seconds. The value -1 indicates always infinite time.

The expiration time of an entry is automatically refreshed when it is got from the map. However, iterators do not need to refresh entries accessed through them.

The maximum number of entries accepted by the map can be specified with max entries. The oldest entries above the limit will be expired indepently on their expiration time. The limit need not to be strict during puts but maintained by the expiration handler.

Note that the size of the map and its sets and collections is not constant in time as entries expire dynamically. Iterators can return expired entries if there is a pause between calls to the hasNext and next methods.

Version:

$Id: Cache.java,v 1.12 2009/09/28 15:08:43 cvsimp Exp $

Author:

Ilkka Priha

Nested Class Summary

Nested classes/interfaces inherited from interface org.norther.tammi.acorn.cache.CachedMap

CachedMap.Value<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Method Summary

Methods inherited from interface org.norther.tammi.acorn.cache.CachedMap

add, add, expire, expireAll, expireFraction, get, getDefaultExpirationTime, getExpirationLimit, getExpirationSleepInterval, getExpirationThreshold, getMaxExpirationTime, isAllowExpired, isAutoRefreshDeclined, isDiscardOverloaded, put, putIfAbsent, refresh, refresh, setAllowExpired, setAutoRefreshDeclined, setDefaultExpirationTime, setDiscardOverloaded, setExpirationLimit, setExpirationSleepInterval, setExpirationThreshold, setMaxExpirationTime

Methods inherited from interface java.util.concurrent.ConcurrentMap

putIfAbsent, remove, replace, replace

Methods inherited from interface java.util.Map

clear, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values