org.hibernate.event.internal.OnUpdateVisitor Maven / Gradle / Ivy
/*
* 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.hibernate.HibernateException;
import org.hibernate.collection.spi.PersistentCollection;
import org.hibernate.event.spi.EventSource;
import org.hibernate.persister.collection.CollectionPersister;
import org.hibernate.type.CollectionType;
/**
* When an entity is passed to update(), we must inspect all its collections and
* 1. associate any uninitialized PersistentCollections with this session
* 2. associate any initialized PersistentCollections with this session, using the
* existing snapshot
* 3. execute a collection removal (SQL DELETE) for each null collection property
* or "new" collection
*
* @author Gavin King
*/
public class OnUpdateVisitor extends ReattachVisitor {
OnUpdateVisitor(EventSource session, Serializable key, Object owner) {
super( session, key, owner );
}
@Override
Object processCollection(Object collection, CollectionType type) throws HibernateException {
if ( collection == CollectionType.UNFETCHED_COLLECTION ) {
return null;
}
EventSource session = getSession();
CollectionPersister persister = session.getFactory().getCollectionPersister( type.getRole() );
final Serializable collectionKey = extractCollectionKeyFromOwner( persister );
if ( collection!=null && (collection instanceof PersistentCollection) ) {
PersistentCollection wrapper = (PersistentCollection) collection;
if ( wrapper.setCurrentSession(session) ) {
//a "detached" collection!
if ( !isOwnerUnchanged( wrapper, persister, collectionKey ) ) {
// if the collection belonged to a different entity,
// clean up the existing state of the collection
removeCollection( persister, collectionKey, session );
}
reattachCollection(wrapper, type);
}
else {
// a collection loaded in the current session
// can not possibly be the collection belonging
// to the entity passed to update()
removeCollection(persister, collectionKey, session);
}
}
else {
// null or brand new collection
// this will also (inefficiently) handle arrays, which have
// no snapshot, so we can't do any better
removeCollection(persister, collectionKey, session);
}
return null;
}
}