org.hibernate.cache.access
Interface EntityRegionAccessStrategy

All Known Implementing Classes:
EntityAccessStrategyAdapter, OptimisticReadOnlyAccess, OptimisticTransactionalAccess, ReadOnlyAccess, TransactionalAccess

public interface EntityRegionAccessStrategy

Contract for managing transactional and concurrent access to cached entity data. The expected call sequences related to various operations are:

There is another usage pattern that is used to invalidate entries after performing "bulk" HQL/SQL operations: lockRegion() -> removeAll() -> unlockRegion(org.hibernate.cache.access.SoftLock)

Author:
Gavin King, Steve Ebersole

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)
          Called after an item has been updated (after the transaction completes), instead of calling release().
 void evict(Object key)
          Forcibly evict an item from the cache immediately without regard for transaction isolation.
 void evictAll()
          Forcibly evict all items from the cache immediately without regard for transaction isolation.
 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)
          Called after an item has been inserted (before the transaction completes), instead of calling evict().
 SoftLock lockItem(Object key, Object version)
          We are going to attempt to update/delete the keyed object.
 SoftLock lockRegion()
          Lock the entire region
 boolean putFromLoad(Object key, Object value, long txTimestamp, Object version)
          Attempt to cache an object, after loading from the database.
 boolean putFromLoad(Object key, Object value, long txTimestamp, Object version, boolean minimalPutOverride)
          Attempt to cache an object, after loading from the database, explicitly specifying the minimalPut behavior.
 void remove(Object key)
          Called after an item has become stale (before the transaction completes).
 void removeAll()
          Called to evict data from 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().
 

Method Detail

getRegion

EntityRegion getRegion()
Get the wrapped entity cache region

Returns:
The underlying region

get

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.

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

boolean putFromLoad(Object key,
                    Object value,
                    long txTimestamp,
                    Object version)
                    throws CacheException
Attempt to cache an object, after loading from the database.

Parameters:
key - The item key
value - The item
txTimestamp - a timestamp prior to the transaction start time
version - the item version number
Returns:
true if the object was successfully cached
Throws:
CacheException - Propogated from underlying Region

putFromLoad

boolean putFromLoad(Object key,
                    Object value,
                    long txTimestamp,
                    Object version,
                    boolean minimalPutOverride)
                    throws CacheException
Attempt to cache an object, after loading from the database, explicitly specifying the minimalPut behavior.

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

lockItem

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

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

SoftLock lockRegion()
                    throws CacheException
Lock the entire region

Returns:
A representation of our lock on the item; or null.
Throws:
CacheException - Propogated from underlying Region

unlockItem

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

Parameters:
key - The item key
lock - The lock previously obtained from lockItem(java.lang.Object, java.lang.Object)
Throws:
CacheException - Propogated from underlying Region

unlockRegion

void unlockRegion(SoftLock lock)
                  throws CacheException
Called after we have finished the attempted invalidation of the entire region

Parameters:
lock - The lock previously obtained from lockRegion()
Throws:
CacheException - Propogated from underlying Region

insert

boolean insert(Object key,
               Object value,
               Object version)
               throws CacheException
Called after an item has been inserted (before the transaction completes), instead of calling evict(). This method is used by "synchronous" concurrency strategies.

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

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.

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

boolean update(Object key,
               Object value,
               Object currentVersion,
               Object previousVersion)
               throws CacheException
Called after an item has been updated (before the transaction completes), instead of calling evict(). This method is used by "synchronous" concurrency strategies.

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

boolean afterUpdate(Object key,
                    Object value,
                    Object currentVersion,
                    Object previousVersion,
                    SoftLock lock)
                    throws CacheException
Called after an item has been updated (after the transaction completes), instead of calling release(). This method is used by "asynchronous" concurrency strategies.

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 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

remove

void remove(Object key)
            throws CacheException
Called after an item has become stale (before the transaction completes). This method is used by "synchronous" concurrency strategies.

Parameters:
key - The key of the item to remove
Throws:
CacheException - Propogated from underlying Region

removeAll

void removeAll()
               throws CacheException
Called to evict data from the entire region

Throws:
CacheException - Propogated from underlying Region

evict

void evict(Object key)
           throws CacheException
Forcibly evict an item from the cache immediately without regard for transaction isolation.

Parameters:
key - The key of the item to remove
Throws:
CacheException - Propogated from underlying Region

evictAll

void evictAll()
              throws CacheException
Forcibly evict all items from the cache immediately without regard for transaction isolation.

Throws:
CacheException - Propogated from underlying Region


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