org.apache.jcs.engine.memory.behavior
Interface IMemoryCache<K extends Serializable,V extends Serializable>

All Known Implementing Classes:

AbstractDoubleLinkedListMemoryCache, AbstractMemoryCache, FIFOMemoryCache, LHMLRUMemoryCache, LRUMemoryCache, MRUMemoryCache

public interface IMemoryCache<K extends Serializable,V extends Serializable>

For the framework. Insures methods a MemoryCache needs to access.

initialize

void initialize(CompositeCache<K,V> cache)

Initialize the memory cache

Parameters:

cache - The cache (region) this memory store is attached to.

dispose

void dispose()
             throws IOException

Destroy the memory cache

Throws:

IOException

getSize

int getSize()

Get the number of elements contained in the memory store

Returns:

Element count

getStatistics

IStats getStatistics()

Returns the historical and statistical data for a region's memory cache.

Returns:

Statistics and Info for the Memory Cache.

getIterator

Iterator<Map.Entry<K,MemoryElementDescriptor<K,V>>> getIterator()

Get an iterator for all elements in the memory cache. This should be removed since it is fairly dangerous. Other classes should not be able to directly access items in the memory cache.

Returns:

An iterator

getKeySet

Set<K> getKeySet()

Get a set of the keys for all elements in the memory cache.

Returns:

a set of the key type

remove

boolean remove(K key)
               throws IOException

Removes an item from the cache

Parameters:

key - Identifies item to be removed

Returns:

Description of the Return Value

Throws:

IOException - Description of the Exception

removeAll

void removeAll()
               throws IOException

Removes all cached items from the cache.

Throws:

IOException - Description of the Exception

freeElements

int freeElements(int numberToFree)
                 throws IOException

This instructs the memory cache to remove the numberToFree according to its eviction policy. For example, the LRUMemoryCache will remove the numberToFree least recently used items. These will be spooled to disk if a disk auxiliary is available.

Parameters:

numberToFree -

Returns:

the number that were removed. if you ask to free 5, but there are only 3, you will get 3.

Throws:

IOException

get

ICacheElement<K,V> get(K key)
                                                                 throws IOException

Get an item from the cache

Parameters:

key - Description of the Parameter

Returns:

Description of the Return Value

Throws:

IOException - Description of the Exception

getMultiple

Map<K,ICacheElement<K,V>> getMultiple(Set<K> keys)
                                                                                                     throws IOException

Gets multiple items from the cache based on the given set of keys.

Parameters:

keys -

Returns:

a map of K key to ICacheElement element, or an empty map if there is no data in cache for any of these keys

Throws:

IOException

getQuiet

ICacheElement<K,V> getQuiet(K key)
                                                                      throws IOException

Get an item from the cache without effecting its order or last access time

Parameters:

key - Description of the Parameter

Returns:

The quiet value

Throws:

IOException - Description of the Exception

waterfal

void waterfal(ICacheElement<K,V> ce)
              throws IOException

Spools the item contained in the provided element to disk

Parameters:

ce - Description of the Parameter

Throws:

IOException - Description of the Exception

update

void update(ICacheElement<K,V> ce)
            throws IOException

Puts an item to the cache.

Parameters:

ce - Description of the Parameter

Throws:

IOException - Description of the Exception

getCacheAttributes

ICompositeCacheAttributes getCacheAttributes()

Returns the CacheAttributes for the region.

Returns:

The cacheAttributes value

setCacheAttributes

void setCacheAttributes(ICompositeCacheAttributes cattr)

Sets the CacheAttributes of the region.

Parameters:

cattr - The new cacheAttributes value

getCompositeCache

CompositeCache<K,V> getCompositeCache()

Gets the cache hub / region that uses the MemoryCache.

Returns:

The cache value

getGroupKeys

Set<K> getGroupKeys(String group)

Gets the set of keys of objects currently in the group.

Parameters:

group -

Returns:

a Set of group keys.

getGroupNames

Set<String> getGroupNames()

Gets the set of group names in the cache

Returns:

a Set of group names.