/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008, Red Hat Middleware LLC 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 Middleware LLC.
*
* 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.def;
import java.io.Serializable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.hibernate.HibernateException;
import org.hibernate.engine.Cascade;
import org.hibernate.engine.CascadingAction;
import org.hibernate.engine.EntityEntry;
import org.hibernate.engine.EntityKey;
import org.hibernate.engine.PersistenceContext;
import org.hibernate.event.EventSource;
import org.hibernate.event.EvictEvent;
import org.hibernate.event.EvictEventListener;
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 Logger log = LoggerFactory.getLogger(DefaultEvictEventListener.class);
/**
* Handle the given evict event.
*
* @param event The evict event to be handled.
* @throws HibernateException
*/
public void onEvict(EvictEvent event) throws HibernateException {
EventSource source = event.getSession();
final Object object = event.getObject();
final PersistenceContext persistenceContext = source.getPersistenceContext();
if ( object instanceof HibernateProxy ) {
LazyInitializer li = ( (HibernateProxy) object ).getHibernateLazyInitializer();
Serializable id = li.getIdentifier();
EntityPersister persister = source.getFactory().getEntityPersister( li.getEntityName() );
if ( id == null ) {
throw new IllegalArgumentException("null identifier");
}
EntityKey key = new EntityKey( id, persister, source.getEntityMode() );
persistenceContext.removeProxy( key );
if ( !li.isUninitialized() ) {
final Object entity = persistenceContext.removeEntity( key );
if ( entity != null ) {
EntityEntry e = event.getSession().getPersistenceContext().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 );
}
}
}
protected void doEvict(
final Object object,
final EntityKey key,
final EntityPersister persister,
final EventSource session)
throws HibernateException {
if ( log.isTraceEnabled() ) {
log.trace( "evicting " + MessageHelper.infoString(persister) );
}
// 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 );
}
}