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

java.lang.Object
  extended by 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()


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