/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008-2011, 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.event.internal;
import java.io.Serializable;
import org.jboss.logging.Logger;
import org.hibernate.HibernateException;
import org.hibernate.engine.internal.Cascade;
import org.hibernate.engine.spi.CascadingAction;
import org.hibernate.engine.spi.EntityEntry;
import org.hibernate.engine.spi.EntityKey;
import org.hibernate.engine.spi.PersistenceContext;
import org.hibernate.event.spi.EventSource;
import org.hibernate.event.spi.EvictEvent;
import org.hibernate.event.spi.EvictEventListener;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.pretty.MessageHelper;
import org.hibernate.proxy.HibernateProxy;
import org.hibernate.proxy.LazyInitializer;
/**
* Defines the default evict event listener used by hibernate for evicting entities
* in response to generated flush events. In particular, this implementation will
* remove any hard references to the entity that are held by the infrastructure
* (references held by application or other persistent instances are okay)
*
* @author Steve Ebersole
*/
public class DefaultEvictEventListener implements EvictEventListener {
private static final CoreMessageLogger LOG = Logger.getMessageLogger(CoreMessageLogger.class,
DefaultEvictEventListener.class.getName());
/**
* Handle the given evict event.
*
* @param event The evict event to be handled.
* @throws HibernateException
*/
public void onEvict(EvictEvent event) throws HibernateException {
final Object object = event.getObject();
if ( object == null ) {
throw new NullPointerException( "null passed to Session.evict()" );
}
final EventSource source = event.getSession();
final PersistenceContext persistenceContext = source.getPersistenceContext();
if ( object instanceof HibernateProxy ) {
final LazyInitializer li = ( (HibernateProxy) object ).getHibernateLazyInitializer();
final Serializable id = li.getIdentifier();
if ( id == null ) {
throw new IllegalArgumentException( "Could not determine identifier of proxy passed to evict()" );
}
final EntityPersister persister = source.getFactory().getEntityPersister( li.getEntityName() );
final EntityKey key = source.generateEntityKey( id, persister );
persistenceContext.removeProxy( key );
if ( !li.isUninitialized() ) {
final Object entity = persistenceContext.removeEntity( key );
if ( entity != null ) {
EntityEntry e = persistenceContext.removeEntry( entity );
doEvict( entity, key, e.getPersister(), event.getSession() );
}
}
li.unsetSession();
}
else {
EntityEntry e = persistenceContext.removeEntry( object );
if ( e != null ) {
persistenceContext.removeEntity( e.getEntityKey() );
doEvict( object, e.getEntityKey(), e.getPersister(), source );
}
else {
// see if the passed object is even an entity, and if not throw an exception
// this is different than legacy Hibernate behavior, but what JPA 2.1 is calling for
// with EntityManager.detach
EntityPersister persister = null;
final String entityName = persistenceContext.getSession().guessEntityName( object );
if ( entityName != null ) {
try {
persister = persistenceContext.getSession().getFactory().getEntityPersister( entityName );
}
catch (Exception ignore) {
}
}
if ( persister == null ) {
throw new IllegalArgumentException( "Non-entity object instance passed to evict : " + object );
}
}
}
}
protected void doEvict(
final Object object,
final EntityKey key,
final EntityPersister persister,
final EventSource session)
throws HibernateException {
if ( LOG.isTraceEnabled() ) {
LOG.tracev( "Evicting {0}", MessageHelper.infoString( persister ) );
}
if ( persister.hasNaturalIdentifier() ) {
session.getPersistenceContext().getNaturalIdHelper().handleEviction( object, persister, key.getIdentifier() );
}
// remove all collections for the entity from the session-level cache
if ( persister.hasCollections() ) {
new EvictVisitor( session ).process( object, persister );
}
// remove any snapshot, not really for memory management purposes, but
// rather because it might now be stale, and there is no longer any
// EntityEntry to take precedence
// This is now handled by removeEntity()
//session.getPersistenceContext().removeDatabaseSnapshot(key);
new Cascade( CascadingAction.EVICT, Cascade.AFTER_EVICT, session )
.cascade( persister, object );
}
}