org.hibernate.cache.jbc2.entity
Class OptimisticReadOnlyAccess

java.lang.Object
  org.hibernate.cache.jbc2.entity.TransactionalAccess
      org.hibernate.cache.jbc2.entity.OptimisticTransactionalAccess
          org.hibernate.cache.jbc2.entity.OptimisticReadOnlyAccess

All Implemented Interfaces:

EntityRegionAccessStrategy

public class OptimisticReadOnlyAccess
extends OptimisticTransactionalAccess

This defines the strategy for read-only access to enity data in an optimistic-locking JBossCache using its 2.x APIs

The read-only access to a JBossCache really is still transactional, just with the extra semantic or guarantee that we will not update data.

Author:

Brian Stansberry

Field Summary

Fields inherited from class org.hibernate.cache.jbc2.entity.TransactionalAccess

region

Constructor Summary

OptimisticReadOnlyAccess(EntityRegionImpl region)

Method Summary

boolean	afterUpdate(Object key, Object value, Object currentVersion, Object previousVersion, SoftLock lock) Called after an item has been updated (after the transaction completes), instead of calling release().
SoftLock	lockItem(Object key, Object version) We are going to attempt to update/delete the keyed object.
SoftLock	lockRegion() Lock the entire region
void	unlockItem(Object key, SoftLock lock) Called when we have finished the attempted update/delete (which may or may not have been successful), after transaction completion.
void	unlockRegion(SoftLock lock) Called after we have finished the attempted invalidation of the entire region
boolean	update(Object key, Object value, Object currentVersion, Object previousVersion) Called after an item has been updated (before the transaction completes), instead of calling evict().

Methods inherited from class org.hibernate.cache.jbc2.entity.TransactionalAccess

afterInsert, evict, evictAll, get, getRegion, insert, putFromLoad, putFromLoad, remove, removeAll

Methods inherited from class java.lang.Object

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

Constructor Detail

OptimisticReadOnlyAccess

public OptimisticReadOnlyAccess(EntityRegionImpl region)

Method Detail

lockItem

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

Description copied from interface: EntityRegionAccessStrategy

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 release(), to release the lock. Concurrency strategies which do not support client-visible locks may silently return null.

Specified by:

lockItem in interface EntityRegionAccessStrategy

Overrides:

lockItem in class TransactionalAccess

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:

CacheException - Propogated from underlying Region

lockRegion

public SoftLock lockRegion()
                    throws CacheException

Description copied from interface: EntityRegionAccessStrategy

Lock the entire region

Specified by:

lockRegion in interface EntityRegionAccessStrategy

Overrides:

lockRegion in class TransactionalAccess

Returns:

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

Throws:

CacheException - Propogated from underlying Region

unlockItem

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

Description copied from interface: EntityRegionAccessStrategy

Called when we have finished the attempted update/delete (which may or may not have been successful), after transaction completion. This method is used by "asynchronous" concurrency strategies.

Specified by:

unlockItem in interface EntityRegionAccessStrategy

Overrides:

unlockItem in class TransactionalAccess

Parameters:

key - The item key

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

Throws:

CacheException - Propogated from underlying Region

unlockRegion

public void unlockRegion(SoftLock lock)
                  throws CacheException

Description copied from interface: EntityRegionAccessStrategy

Called after we have finished the attempted invalidation of the entire region

Specified by:

unlockRegion in interface EntityRegionAccessStrategy

Overrides:

unlockRegion in class TransactionalAccess

Parameters:

lock - The lock previously obtained from EntityRegionAccessStrategy.lockRegion()

Throws:

CacheException - Propogated from underlying Region

update

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

Description copied from interface: EntityRegionAccessStrategy

Called after an item has been updated (before the transaction completes), instead of calling evict(). This method is used by "synchronous" concurrency strategies.

Specified by:

update in interface EntityRegionAccessStrategy

Overrides:

update in class TransactionalAccess

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:

CacheException - Propogated from underlying Region

afterUpdate

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

Description copied from interface: EntityRegionAccessStrategy

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

Specified by:

afterUpdate in interface EntityRegionAccessStrategy

Overrides:

afterUpdate in class TransactionalAccess

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 EntityRegionAccessStrategy.lockItem(java.lang.Object, java.lang.Object)

Returns:

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

Throws:

CacheException - Propogated from underlying Region