net.sf.ehcache.store
Class LegacyStoreWrapper

java.lang.Object
  net.sf.ehcache.store.AbstractStore
      net.sf.ehcache.store.LegacyStoreWrapper

All Implemented Interfaces:

Store

public class LegacyStoreWrapper
extends AbstractStore

A wrapper to convert a legacy pair of stores into a new style compound store.

Author:

Chris Dennis

Field Summary

Fields inherited from class net.sf.ehcache.store.AbstractStore

attributeExtractors, searchManager

Fields inherited from interface net.sf.ehcache.store.Store

CLUSTER_COHERENT, NODE_COHERENT

Constructor Summary

LegacyStoreWrapper(Store memory, Store disk, RegisteredEventListeners eventListeners, CacheConfiguration config)
Create a correctly locked store wrapper around the supplied in-memory and on disk stores.

Method Summary

boolean	bufferFull() Some store types, such as the disk stores can fill their write buffers if puts come in too fast.
boolean	containsKey(Object key) A check to see if a key is in the Store.
boolean	containsKeyInMemory(Object key) A check to see if a key is in the Store and is currently held in memory.
boolean	containsKeyOffHeap(Object key) A check to see if a key is in the Store and is currently held off-heap.
boolean	containsKeyOnDisk(Object key) A check to see if a key is in the Store and is currently held on disk.
void	dispose() Prepares for shutdown.
void	expireElements() Expire all elements.
void	flush() Flush elements to persistent store.
Element	get(Object key) Gets an item from the cache.
Policy	getInMemoryEvictionPolicy()
int	getInMemorySize() Returns the current local in-memory store size
long	getInMemorySizeInBytes() Gets the size of the in-memory portion of the store, in bytes.
Object	getInternalContext() This should not be used, and will generally return null
List	getKeys() Gets an Array of the keys for all elements in the disk store.
Object	getMBean() Optional implementation specific MBean exposed by the store.
Store	getMemoryStore() Returns the underlying memory store for this legacy wrapper.
int	getOffHeapSize() Returns the current local off-heap store size
long	getOffHeapSizeInBytes() Gets the size of the off-heap portion of the store, in bytes.
int	getOnDiskSize() Returns the current local on-disk store size
long	getOnDiskSizeInBytes() Gets the size of the on-disk portion of the store, in bytes.
Element	getQuiet(Object key) Gets an Element from the Store, without updating statistics
int	getSize() Returns the current local store size
Status	getStatus() Returns the cache status.
int	getTerracottaClusteredSize() Returns the current Terracotta clustered store size
boolean	put(Element element) Puts an item into the store.
Element	putIfAbsent(Element element) Put an element in the store if no element is currently mapped to the elements key.
boolean	putWithWriter(Element element, CacheWriterManager writerManager) Puts an item into the store and the cache writer manager in an atomic operation
Element	remove(Object key) Removes an item from the cache.
void	removeAll() Remove all of the elements from the store.
Element	removeElement(Element element, ElementValueComparator comparator) Remove the Element mapped to the key for the supplied element if the value of the supplied Element is equal to the value of the cached Element.
Element	removeWithWriter(Object key, CacheWriterManager writerManager) Removes an item from the store and the cache writer manager in an atomic operation.
Element	replace(Element element) Replace the cached element only if an Element is currently cached for this key
boolean	replace(Element old, Element element, ElementValueComparator comparator) Replace the cached element only if the value of the current Element is equal to the value of the supplied old Element.
void	setInMemoryEvictionPolicy(Policy policy) Sets the eviction policy strategy.

Methods inherited from class net.sf.ehcache.store.AbstractStore

addStoreListener, executeQuery, getAll, getAllQuiet, getEventListenerList, getSearchAttribute, getSearchAttributes, hasAbortedSizeOf, isCacheCoherent, isClusterCoherent, isNodeCoherent, putAll, recalculateSize, removeAll, removeStoreListener, setAttributeExtractors, setNodeCoherent, waitUntilClusterCoherent

Methods inherited from class java.lang.Object

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

Constructor Detail

LegacyStoreWrapper

public LegacyStoreWrapper(Store memory,
                          Store disk,
                          RegisteredEventListeners eventListeners,
                          CacheConfiguration config)

Create a correctly locked store wrapper around the supplied in-memory and on disk stores.

Parameters:

memory - in-memory store

disk - on disk store

eventListeners - event listener to fire on

config - cache configuration

Method Detail

bufferFull

public boolean bufferFull()

Some store types, such as the disk stores can fill their write buffers if puts come in too fast. The thread will wait for a short time before checking again.

Returns:

true if the store write buffer is backed up.

containsKey

public boolean containsKey(Object key)

A check to see if a key is in the Store.

Parameters:

key - The Element key

Returns:

true if found. No check is made to see if the Element is expired. 1.2

containsKeyInMemory

public boolean containsKeyInMemory(Object key)

A check to see if a key is in the Store and is currently held in memory.

Parameters:

key - The Element key

Returns:

true if found. No check is made to see if the Element is expired.

containsKeyOffHeap

public boolean containsKeyOffHeap(Object key)

A check to see if a key is in the Store and is currently held off-heap.

Parameters:

key - The Element key

Returns:

true if found. No check is made to see if the Element is expired.

containsKeyOnDisk

public boolean containsKeyOnDisk(Object key)

A check to see if a key is in the Store and is currently held on disk.

Parameters:

key - The Element key

Returns:

true if found. No check is made to see if the Element is expired.

dispose

public void dispose()

Prepares for shutdown.

expireElements

public void expireElements()

Expire all elements.

flush

public void flush()
           throws IOException

Flush elements to persistent store.

Throws:

IOException - if any IO error occurs

get

public Element get(Object key)

Gets an item from the cache.

getInMemoryEvictionPolicy

public Policy getInMemoryEvictionPolicy()

Returns:

the current eviction policy. This may not be the configured policy, if it has been dynamically set.

See Also:

Store.setInMemoryEvictionPolicy(Policy)

getInMemorySize

public int getInMemorySize()

Returns the current local in-memory store size

Returns:

the count of the Elements in the Store and in-memory on the local machine

getInMemorySizeInBytes

public long getInMemorySizeInBytes()

Gets the size of the in-memory portion of the store, in bytes.

This method may be expensive to run, depending on implementation. Implementers may choose to return an approximate size.

Returns:

the approximate in-memory size of the store in bytes

getInternalContext

public Object getInternalContext()

This should not be used, and will generally return null

Returns:

some internal context (probably null)

getKeys

public List getKeys()

Gets an Array of the keys for all elements in the disk store.

Returns:

An List of Serializable keys

getOffHeapSize

public int getOffHeapSize()

Returns the current local off-heap store size

Returns:

the count of the Elements in the Store and off-heap on the local machine

getOffHeapSizeInBytes

public long getOffHeapSizeInBytes()

Gets the size of the off-heap portion of the store, in bytes.

Returns:

the approximate off-heap size of the store in bytes

getOnDiskSize

public int getOnDiskSize()

Returns the current local on-disk store size

Returns:

the count of the Elements in the Store and on-disk on the local machine

getOnDiskSizeInBytes

public long getOnDiskSizeInBytes()

Gets the size of the on-disk portion of the store, in bytes.

Returns:

the on-disk size of the store in bytes

getQuiet

public Element getQuiet(Object key)

Gets an Element from the Store, without updating statistics

Returns:

The element

getSize

public int getSize()

Returns the current local store size

The size is the number of Elements in the memory store plus the number of Elements in the disk store.

Returns:

the count of the Elements in the Store on the local machine

getStatus

public Status getStatus()

Returns the cache status.

getTerracottaClusteredSize

public int getTerracottaClusteredSize()

Returns the current Terracotta clustered store size

Returns:

the count of the Elements in the Store across the cluster

put

public boolean put(Element element)
            throws CacheException

Puts an item into the store.

Returns:

true if this is a new put for the key or element is null. Returns false if it was an update.

Throws:

CacheException

putWithWriter

public boolean putWithWriter(Element element,
                             CacheWriterManager writerManager)
                      throws CacheException

Puts an item into the store and the cache writer manager in an atomic operation

Returns:

true if this is a new put for the key or element is null. Returns false if it was an update.

Throws:

CacheException

remove

public Element remove(Object key)

Removes an item from the cache.

removeAll

public void removeAll()
               throws CacheException

Remove all of the elements from the store.

If there are registered CacheEventListeners they are notified of the expiry or removal of the Element as each is removed.

Throws:

CacheException

removeWithWriter

public Element removeWithWriter(Object key,
                                CacheWriterManager writerManager)
                         throws CacheException

Removes an item from the store and the cache writer manager in an atomic operation.

Throws:

CacheException

setInMemoryEvictionPolicy

public void setInMemoryEvictionPolicy(Policy policy)

Sets the eviction policy strategy. The Store will use a policy at startup. The store may allow changing the eviction policy strategy dynamically. Otherwise implementations will throw an exception if this method is called.

Parameters:

policy - the new policy

getMemoryStore

public Store getMemoryStore()

Returns the underlying memory store for this legacy wrapper.

putIfAbsent

public Element putIfAbsent(Element element)
                    throws NullPointerException

Put an element in the store if no element is currently mapped to the elements key.

Parameters:

element - element to be added

Returns:

the element previously cached for this key, or null if none.

Throws:

NullPointerException - if the element is null, or has a null key

removeElement

public Element removeElement(Element element,
                             ElementValueComparator comparator)
                      throws NullPointerException

Remove the Element mapped to the key for the supplied element if the value of the supplied Element is equal to the value of the cached Element. This is a CAS operation. It is consistent even against a distributed cache that is not coherent. If the old value is stale when this operation is attempted the remove does not take place.

Parameters:

element - Element to be removed

comparator - ElementValueComparator to use to compare elements

Returns:

the Element removed or null if no Element was removed

Throws:

NullPointerException - if the element is null, or has a null key

replace

public boolean replace(Element old,
                       Element element,
                       ElementValueComparator comparator)
                throws NullPointerException,
                       IllegalArgumentException

Replace the cached element only if the value of the current Element is equal to the value of the supplied old Element.

Parameters:

old - Element to be test against

element - Element to be cached

comparator - ElementValueComparator to use to compare elements

Returns:

true is the Element was replaced

Throws:

NullPointerException - if the either Element is null or has a null key

IllegalArgumentException - if the two Element keys are non-null but not equal

replace

public Element replace(Element element)
                throws NullPointerException

Replace the cached element only if an Element is currently cached for this key

Parameters:

element - Element to be cached

Returns:

the Element previously cached for this key, or null if no Element was cached

Throws:

NullPointerException - if the Element is null or has a null key

getMBean

public Object getMBean()

Optional implementation specific MBean exposed by the store.

Returns:

implementation specific management bean