net.sf.ehcache.store.compound.impl
Class OverflowToDiskStore

java.lang.Object
  net.sf.ehcache.store.AbstractStore
      net.sf.ehcache.store.compound.CompoundStore
          net.sf.ehcache.store.compound.impl.OverflowToDiskStore

All Implemented Interfaces:

CacheConfigurationListener, Store

public final class OverflowToDiskStore
extends CompoundStore
implements CacheConfigurationListener

Implements an overflow-to-disk store.

When this store's in-memory space becomes full, it pushes Elements off to disk.

Author:

Chris Dennis

Field Summary

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

CLUSTER_COHERENT, NODE_COHERENT

Method Summary

boolean	bufferFull() Some store types, such as the disk stores can fill their write buffers if puts come in too fast.
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.
static OverflowToDiskStore	create(Cache cache, String diskStorePath) Constructs an overflow-to-disk store for the given cache, using the given disk path.
void	deregistered(CacheConfiguration config) Indicates that this listener was removed from the given configuration
void	diskCapacityChanged(int oldCapacity, int newCapacity) Indicates a change in the configurations disk store capacity
void	expireElements() Expire all elements.
void	flush() Flush elements to persistent store.
File	getDataFile() Return a reference to the file backing this store.
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	getMBean() Optional implementation specific MBean exposed by the store.
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.
int	getTerracottaClusteredSize() Returns the current Terracotta clustered store size
void	loggingChanged(boolean oldValue, boolean newValue) Indicates a change in the configuration for enable/disable logging
void	memoryCapacityChanged(int oldCapacity, int newCapacity) Indicates a change in the configurations memory store capacity
void	registered(CacheConfiguration config) Indicates that this listener was registered with the given configuration
void	setInMemoryEvictionPolicy(Policy policy) Sets the eviction policy strategy.
void	timeToIdleChanged(long oldTimeToIdle, long newTimeToIdle) Indicates a change in the configurations time to idle
void	timeToLiveChanged(long oldTimeToLive, long newTimeToLive) Indicates a change in the configurations time to live

Methods inherited from class net.sf.ehcache.store.compound.CompoundStore

containsKey, dispose, elementSet, evict, fault, get, getInternalContext, getKeys, getQuiet, getRandomSample, getSize, getStatus, keySet, put, putIfAbsent, putRawIfAbsent, putWithWriter, remove, removeAll, removeElement, removeWithWriter, replace, replace, tryFault, unretrievedGet

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

addStoreListener, executeQuery, getEventListenerList, getSearchAttribute, isCacheCoherent, isClusterCoherent, isNodeCoherent, removeStoreListener, setAttributeExtractors, setNodeCoherent, waitUntilClusterCoherent

Methods inherited from class java.lang.Object

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

Method Detail

create

public static OverflowToDiskStore create(Cache cache,
                                         String diskStorePath)

Constructs an overflow-to-disk store for the given cache, using the given disk path.

Parameters:

cache - cache that fronts this store

diskStorePath - disk path to store data in

Returns:

a fully initialized store

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.

Specified by:

bufferFull in interface Store

Returns:

true if the store write buffer is backed up.

containsKeyInMemory

public boolean containsKeyInMemory(Object key)

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

Specified by:

containsKeyInMemory in interface Store

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.

Specified by:

containsKeyOffHeap in interface Store

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.

Specified by:

containsKeyOnDisk in interface Store

Parameters:

key - The Element key

Returns:

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

getInMemorySize

public int getInMemorySize()

Returns the current local in-memory store size

Specified by:

getInMemorySize in interface Store

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.

Specified by:

getInMemorySizeInBytes in interface Store

Returns:

the approximate in-memory size of the store in bytes

getOffHeapSize

public int getOffHeapSize()

Returns the current local off-heap store size

Specified by:

getOffHeapSize in interface Store

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.

Specified by:

getOffHeapSizeInBytes in interface Store

Returns:

the approximate off-heap size of the store in bytes

getOnDiskSize

public int getOnDiskSize()

Returns the current local on-disk store size

Specified by:

getOnDiskSize in interface Store

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.

Specified by:

getOnDiskSizeInBytes in interface Store

Returns:

the on-disk size of the store in bytes

getInMemoryEvictionPolicy

public Policy getInMemoryEvictionPolicy()

Specified by:

getInMemoryEvictionPolicy in interface Store

Returns:

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

See Also:

Store.setInMemoryEvictionPolicy(Policy)

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.

Specified by:

setInMemoryEvictionPolicy in interface Store

Parameters:

policy - the new policy

diskCapacityChanged

public void diskCapacityChanged(int oldCapacity,
                                int newCapacity)

Indicates a change in the configurations disk store capacity

Specified by:

diskCapacityChanged in interface CacheConfigurationListener

Parameters:

oldCapacity - previous capacity

newCapacity - new capacity

memoryCapacityChanged

public void memoryCapacityChanged(int oldCapacity,
                                  int newCapacity)

Indicates a change in the configurations memory store capacity

Specified by:

memoryCapacityChanged in interface CacheConfigurationListener

Parameters:

oldCapacity - previous capacity

newCapacity - new capacity

loggingChanged

public void loggingChanged(boolean oldValue,
                           boolean newValue)

Indicates a change in the configuration for enable/disable logging

A NO-OP

Specified by:

loggingChanged in interface CacheConfigurationListener

Parameters:

oldValue - old value whether logging was enabled or not

newValue - new value whether logging was enabled or not

registered

public void registered(CacheConfiguration config)

Indicates that this listener was registered with the given configuration

A NO-OP

Specified by:

registered in interface CacheConfigurationListener

deregistered

public void deregistered(CacheConfiguration config)

Indicates that this listener was removed from the given configuration

A NO-OP

Specified by:

deregistered in interface CacheConfigurationListener

timeToIdleChanged

public void timeToIdleChanged(long oldTimeToIdle,
                              long newTimeToIdle)

Indicates a change in the configurations time to idle

A NO-OP

Specified by:

timeToIdleChanged in interface CacheConfigurationListener

Parameters:

oldTimeToIdle - previous time to idle value

newTimeToIdle - new time to idle value

timeToLiveChanged

public void timeToLiveChanged(long oldTimeToLive,
                              long newTimeToLive)

Indicates a change in the configurations time to live

A NO-OP

Specified by:

timeToLiveChanged in interface CacheConfigurationListener

Parameters:

oldTimeToLive - previous time to live value

newTimeToLive - new time to live value

expireElements

public void expireElements()

Expire all elements.

Specified by:

expireElements in interface Store

flush

public void flush()
           throws IOException

Flush elements to persistent store.

This store is not persistent, so this simply clears the in-memory store if clear-on-flush is set for this cache.

Specified by:

flush in interface Store

Throws:

IOException - if any IO error occurs

getTerracottaClusteredSize

public int getTerracottaClusteredSize()

Returns the current Terracotta clustered store size

Specified by:

getTerracottaClusteredSize in interface Store

Returns:

the count of the Elements in the Store across the cluster

getDataFile

public File getDataFile()

Return a reference to the file backing this store.

getMBean

public Object getMBean()

Optional implementation specific MBean exposed by the store.

Specified by:

getMBean in interface Store

Returns:

implementation specific management bean