org.hibernate.cache.ehcache.internal.strategy
Class ReadOnlyEhcacheEntityRegionAccessStrategy

java.lang.Object
  org.hibernate.cache.ehcache.internal.strategy.ReadOnlyEhcacheEntityRegionAccessStrategy

All Implemented Interfaces:

EntityRegionAccessStrategy, RegionAccessStrategy

public class ReadOnlyEhcacheEntityRegionAccessStrategy
extends Object
implements EntityRegionAccessStrategy

Ehcache specific read-only entity region access strategy

Field Summary

protected T	region The wrapped Hibernate cache region.
protected Settings	settings The settings for this persistence unit.

Constructor Summary

ReadOnlyEhcacheEntityRegionAccessStrategy(EhcacheEntityRegion region, Settings settings)
Create a read-only access strategy accessing the given entity region.

Method Summary

boolean	afterInsert(Object key, Object value, Object version) Called after an item has been inserted (after the transaction completes), instead of calling release().
boolean	afterUpdate(Object key, Object value, Object currentVersion, Object previousVersion, SoftLock lock) Throws UnsupportedOperationException since this cache is read-only
void	evict(Object key) Remove the given mapping without regard to transactional safety
void	evictAll() Remove all mappings without regard to transactional safety
Object	get(Object key, long txTimestamp) Attempt to retrieve an object from the cache.
EntityRegion	getRegion() Get the wrapped entity cache region
boolean	insert(Object key, Object value, Object version) This cache is asynchronous hence a no-op
SoftLock	lockItem(Object key, Object version) We are going to attempt to update/delete the keyed object.
SoftLock	lockRegion() Region locks are not supported.
boolean	putFromLoad(Object key, Object value, long txTimestamp, Object version) This method is a placeholder for method signatures supplied by interfaces pulled in further down the class hierarchy.
boolean	putFromLoad(Object key, Object value, long txTimestamp, Object version, boolean minimalPutOverride) This method is a placeholder for method signatures supplied by interfaces pulled in further down the class hierarchy.
void	remove(Object key) A no-op since this is an asynchronous cache access strategy.
void	removeAll() Called to evict data from the entire region
void	unlockItem(Object key, SoftLock lock) A no-op since this cache is read-only
void	unlockRegion(SoftLock lock) Region locks are not supported - perform a cache clear as a precaution.
boolean	update(Object key, Object value, Object currentVersion, Object previousVersion) Throws UnsupportedOperationException since this cache is read-only

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.hibernate.cache.spi.access.RegionAccessStrategy

evict, evictAll, lockRegion, putFromLoad, remove, removeAll, unlockRegion

Field Detail

region

protected final T extends EhcacheTransactionalDataRegion region

The wrapped Hibernate cache region.

settings

protected final Settings settings

The settings for this persistence unit.

Constructor Detail

ReadOnlyEhcacheEntityRegionAccessStrategy

public ReadOnlyEhcacheEntityRegionAccessStrategy(EhcacheEntityRegion region,
                                                 Settings settings)

Create a read-only access strategy accessing the given entity region.

Method Detail

getRegion

public EntityRegion getRegion()

Get the wrapped entity cache region

Specified by:

getRegion in interface EntityRegionAccessStrategy

Returns:

The underlying region

get

public Object get(Object key,
                  long txTimestamp)
           throws CacheException

Attempt to retrieve an object from the cache. Mainly used in attempting to resolve entities/collections from the second level cache.

Specified by:

get in interface RegionAccessStrategy

Parameters:

key - The key of the item to be retrieved.

txTimestamp - a timestamp prior to the transaction start time

Returns:

the cached object or null

Throws:

CacheException - Propogated from underlying Region

putFromLoad

public boolean putFromLoad(Object key,
                           Object value,
                           long txTimestamp,
                           Object version,
                           boolean minimalPutOverride)
                    throws CacheException

This method is a placeholder for method signatures supplied by interfaces pulled in further down the class hierarchy.

Specified by:

putFromLoad in interface RegionAccessStrategy

Parameters:

key - The item key

value - The item

txTimestamp - a timestamp prior to the transaction start time

version - the item version number

minimalPutOverride - Explicit minimalPut flag

Returns:

true if the object was successfully cached

Throws:

CacheException - Propogated from underlying Region

See Also:

RegionAccessStrategy.putFromLoad(java.lang.Object, java.lang.Object, long, java.lang.Object, boolean), RegionAccessStrategy.putFromLoad(java.lang.Object, java.lang.Object, long, java.lang.Object, boolean)

lockItem

public SoftLock lockItem(Object key,
                         Object version)
                  throws UnsupportedOperationException

Description copied from interface: RegionAccessStrategy

We are going to attempt to update/delete the keyed object. This method is used by "asynchronous" concurrency strategies.

The returned object must be passed back to RegionAccessStrategy.unlockItem(java.lang.Object, org.hibernate.cache.spi.access.SoftLock), to release the lock. Concurrency strategies which do not support client-visible locks may silently return null.

Specified by:

lockItem in interface RegionAccessStrategy

Parameters:

key - The key of the item to lock

version - The item's current version value

Returns:

A representation of our lock on the item; or null.

Throws:

UnsupportedOperationException

unlockItem

public void unlockItem(Object key,
                       SoftLock lock)
                throws CacheException

A no-op since this cache is read-only

Specified by:

unlockItem in interface RegionAccessStrategy

Parameters:

key - The item key

lock - The lock previously obtained from RegionAccessStrategy.lockItem(java.lang.Object, java.lang.Object)

Throws:

CacheException - Propogated from underlying Region

insert

public boolean insert(Object key,
                      Object value,
                      Object version)
               throws CacheException

This cache is asynchronous hence a no-op

Specified by:

insert in interface EntityRegionAccessStrategy

Parameters:

key - The item key

value - The item

version - The item's version value

Returns:

Were the contents of the cache actual changed by this operation?

Throws:

CacheException - Propogated from underlying Region

afterInsert

public boolean afterInsert(Object key,
                           Object value,
                           Object version)
                    throws CacheException

Called after an item has been inserted (after the transaction completes), instead of calling release(). This method is used by "asynchronous" concurrency strategies.

Specified by:

afterInsert in interface EntityRegionAccessStrategy

Parameters:

key - The item key

value - The item

version - The item's version value

Returns:

Were the contents of the cache actual changed by this operation?

Throws:

CacheException - Propogated from underlying Region

update

public boolean update(Object key,
                      Object value,
                      Object currentVersion,
                      Object previousVersion)
               throws UnsupportedOperationException

Throws UnsupportedOperationException since this cache is read-only

Specified by:

update in interface EntityRegionAccessStrategy

Parameters:

key - The item key

value - The item

currentVersion - The item's current version value

previousVersion - The item's previous version value

Returns:

Were the contents of the cache actual changed by this operation?

Throws:

UnsupportedOperationException - always

afterUpdate

public boolean afterUpdate(Object key,
                           Object value,
                           Object currentVersion,
                           Object previousVersion,
                           SoftLock lock)
                    throws UnsupportedOperationException

Throws UnsupportedOperationException since this cache is read-only

Specified by:

afterUpdate in interface EntityRegionAccessStrategy

Parameters:

key - The item key

value - The item

currentVersion - The item's current version value

previousVersion - The item's previous version value

lock - The lock previously obtained from RegionAccessStrategy.lockItem(java.lang.Object, java.lang.Object)

Returns:

Were the contents of the cache actual changed by this operation?

Throws:

UnsupportedOperationException - always

putFromLoad

public final boolean putFromLoad(Object key,
                                 Object value,
                                 long txTimestamp,
                                 Object version)
                          throws CacheException

This method is a placeholder for method signatures supplied by interfaces pulled in further down the class hierarchy.

Throws:

CacheException

See Also:

RegionAccessStrategy.putFromLoad(java.lang.Object, java.lang.Object, long, java.lang.Object), RegionAccessStrategy.putFromLoad(java.lang.Object, java.lang.Object, long, java.lang.Object)

lockRegion

public final SoftLock lockRegion()

Region locks are not supported.

Returns:

null

See Also:

RegionAccessStrategy.lockRegion(), RegionAccessStrategy.lockRegion()

unlockRegion

public final void unlockRegion(SoftLock lock)
                        throws CacheException

Region locks are not supported - perform a cache clear as a precaution.

Throws:

CacheException

See Also:

RegionAccessStrategy.unlockRegion(org.hibernate.cache.spi.access.SoftLock), RegionAccessStrategy.unlockRegion(org.hibernate.cache.spi.access.SoftLock)

remove

public void remove(Object key)
            throws CacheException

A no-op since this is an asynchronous cache access strategy.

Throws:

CacheException

See Also:

RegionAccessStrategy.remove(java.lang.Object), RegionAccessStrategy.remove(java.lang.Object)

removeAll

public final void removeAll()
                     throws CacheException

Called to evict data from the entire region

Throws:

CacheException - Propogated from underlying Region

See Also:

RegionAccessStrategy.removeAll(), RegionAccessStrategy.removeAll()

evict

public final void evict(Object key)
                 throws CacheException

Remove the given mapping without regard to transactional safety

Throws:

CacheException

See Also:

RegionAccessStrategy.evict(java.lang.Object), RegionAccessStrategy.evict(java.lang.Object)

evictAll

public final void evictAll()
                    throws CacheException

Remove all mappings without regard to transactional safety

Throws:

CacheException

See Also:

RegionAccessStrategy.evictAll(), RegionAccessStrategy.evictAll()