Class AgingCache<T extends Cacheable>

java.lang.Object

org.deltava.util.cache.Cache<T>

org.deltava.util.cache.AgingCache<T>

Type Parameters:

T - the Cacheable object type

public class AgingCache<T extends Cacheable>
extends Cache<T>

An object cache that supports creation dates. The major difference between this cache and a ExpiringCache is that this cache does not purge an entry until the cache overflows, whereas an ExpiringCache invalidates data based on age.

Since:

1.0

Version:

7.2

Author:

Luke

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	AgingCache.AgingCacheEntry<U extends T>	A cache entry for Aging caches.
protected class	AgingCache.AgingNullCacheEntry<U extends T>	A null cache entry for Aging caches.

Field Summary

Fields

Modifier and Type	Field	Description
protected long	_lastCreationTime

Fields inherited from class Cache

_cache

Modifier and Type	Field	Description
protected final ConcurrentMap<Object, CacheEntry<T>>	_cache

Constructor Summary

Constructors

Constructor	Description
AgingCache(int maxSize)	Creates a new aging cache.

Method Summary

Modifier and Type	Method	Description
protected void	addEntry(T obj)	Adds an entry to the cache.
protected void	addNullEntry(Object key)	Adds a null entry to the cache.
T	get(Object key)	Returns an entry from the cache.

Methods inherited from class Cache

add, addAll, addNull, checkOverflow, clear, contains, getAll, getErrors, getHits, getMaxSize, getRequests, hit, isRemote, remove, request, setMaxSize, size

Modifier and Type	Method	Description
final void	add(T entry)	Adds an entry to the cache.
void	addAll(Collection<? extends T> entries)	Adds a number of entries to the cache.
final void	addNull(String key)	Adds a null entry to the cache.
protected void	checkOverflow()	Automatically resizes the cache in the case of an overflow.
void	clear()	Clears the cache.
boolean	contains(Object key)	Returns if the cache contains a particular cache key.
Map<Object,T>	getAll(Collection<?> keys)	Returns multiple objects from the cache.
long	getErrors()	Returns the total number of cache errors.
final long	getHits()	Returns the total number of cache hits.
int	getMaxSize()	Returns the maximum size of the cache.
final long	getRequests()	Returns the total number of cache requests.
protected void	hit()	Log a cache hit.
boolean	isRemote()	Returns if the cache is a remote cache.
void	remove(Object key)	Invalidate a cache entry.
protected void	request()	Log a cache request.
final void	setMaxSize(int size)	Sets the maximum size of the cache.
int	size()	Returns the current size of the cache.

Methods inherited from class Object

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

Field Details

_lastCreationTime

protected long _lastCreationTime

Constructor Details

AgingCache

public AgingCache(int maxSize)

Creates a new aging cache.

Parameters:

maxSize - the maximum size of the cache

Throws:

IllegalArgumentException - if maxSize is zero or negative

See Also:

• Cache.setMaxSize(int)

Method Details

addEntry

protected void addEntry(T obj)

Adds an entry to the cache.

Specified by:

addEntry in class Cache<T extends Cacheable>

Parameters:

obj - the entry to add to the cache

addNullEntry

protected void addNullEntry(Object key)

Adds a null entry to the cache.

Specified by:

addNullEntry in class Cache<T extends Cacheable>

Parameters:

key - the entry key

get

public T get(Object key)

Returns an entry from the cache.

Specified by:

get in class Cache<T extends Cacheable>

Parameters:

key - the cache key

Returns:

the cache entry, or null if not present