/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.dialect.lock;
import java.io.Serializable;
import org.hibernate.HibernateException;
import org.hibernate.LockMode;
import org.hibernate.OptimisticLockException;
import org.hibernate.action.internal.EntityVerifyVersionProcess;
import org.hibernate.engine.spi.EntityEntry;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.event.spi.EventSource;
import org.hibernate.persister.entity.Lockable;
/**
* An optimistic locking strategy that verifies that the version hasn't changed (prior to transaction commit).
* <p/>
* This strategy is valid for LockMode.OPTIMISTIC
*
* @author Scott Marlow
* @since 3.5
*/
public class OptimisticLockingStrategy implements LockingStrategy {
private final Lockable lockable;
private final LockMode lockMode;
/**
* Construct locking strategy.
*
* @param lockable The metadata for the entity to be locked.
* @param lockMode Indicates the type of lock to be acquired.
*/
public OptimisticLockingStrategy(Lockable lockable, LockMode lockMode) {
this.lockable = lockable;
this.lockMode = lockMode;
if ( lockMode.lessThan( LockMode.OPTIMISTIC ) ) {
throw new HibernateException( "[" + lockMode + "] not valid for [" + lockable.getEntityName() + "]" );
}
}
@Override
public void lock(Serializable id, Object version, Object object, int timeout, SessionImplementor session) {
if ( !lockable.isVersioned() ) {
throw new OptimisticLockException( object, "[" + lockMode + "] not supported for non-versioned entities [" + lockable.getEntityName() + "]" );
}
EntityEntry entry = session.getPersistenceContext().getEntry(object);
EventSource source = (EventSource)session;
EntityVerifyVersionProcess verifyVersion = new EntityVerifyVersionProcess(object, entry);
// Register the EntityVerifyVersionProcess action to run just prior to transaction commit.
source.getActionQueue().registerProcess(verifyVersion);
}
protected LockMode getLockMode() {
return lockMode;
}
}