org.hibernate.cache.ehcache.internal.strategy.ReadWriteEhcacheEntityRegionAccessStrategy Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or .
*/
package org.hibernate.cache.ehcache.internal.strategy;
import org.hibernate.boot.spi.SessionFactoryOptions;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.ehcache.internal.regions.EhcacheEntityRegion;
import org.hibernate.cache.spi.EntityRegion;
import org.hibernate.cache.spi.access.EntityRegionAccessStrategy;
import org.hibernate.cache.spi.access.SoftLock;
/**
* Ehcache specific read/write entity region access strategy
*
* @author Chris Dennis
* @author Alex Snaps
*/
public class ReadWriteEhcacheEntityRegionAccessStrategy
extends AbstractReadWriteEhcacheAccessStrategy
implements EntityRegionAccessStrategy {
/**
* Create a read/write access strategy accessing the given entity region.
*
* @param region The wrapped region
* @param settings The Hibernate settings
*/
public ReadWriteEhcacheEntityRegionAccessStrategy(EhcacheEntityRegion region, SessionFactoryOptions settings) {
super( region, settings );
}
@Override
public EntityRegion getRegion() {
return region();
}
/**
* {@inheritDoc}
*
* A no-op since this is an asynchronous cache access strategy.
*/
@Override
public boolean insert(Object key, Object value, Object version) throws CacheException {
return false;
}
/**
* {@inheritDoc}
*
* Inserts will only succeed if there is no existing value mapped to this key.
*/
@Override
public boolean afterInsert(Object key, Object value, Object version) throws CacheException {
region().writeLock( key );
try {
final Lockable item = (Lockable) region().get( key );
if ( item == null ) {
region().put( key, new Item( value, version, region().nextTimestamp() ) );
return true;
}
else {
return false;
}
}
finally {
region().writeUnlock( key );
}
}
/**
* {@inheritDoc}
*
* A no-op since this is an asynchronous cache access strategy.
*/
@Override
public boolean update(Object key, Object value, Object currentVersion, Object previousVersion)
throws CacheException {
return false;
}
/**
* {@inheritDoc}
*
* Updates will only succeed if this entry was locked by this transaction and exclusively this transaction for the
* duration of this transaction. It is important to also note that updates will fail if the soft-lock expired during
* the course of this transaction.
*/
@Override
public boolean afterUpdate(Object key, Object value, Object currentVersion, Object previousVersion, SoftLock lock)
throws CacheException {
//what should we do with previousVersion here?
region().writeLock( key );
try {
final Lockable item = (Lockable) region().get( key );
if ( item != null && item.isUnlockable( lock ) ) {
final Lock lockItem = (Lock) item;
if ( lockItem.wasLockedConcurrently() ) {
decrementLock( key, lockItem );
return false;
}
else {
region().put( key, new Item( value, currentVersion, region().nextTimestamp() ) );
return true;
}
}
else {
handleLockExpiry( key, item );
return false;
}
}
finally {
region().writeUnlock( key );
}
}
}