/*
* 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.action.internal;
import java.io.Serializable;
import org.hibernate.AssertionFailure;
import org.hibernate.HibernateException;
import org.hibernate.collection.spi.PersistentCollection;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.event.service.spi.EventListenerGroup;
import org.hibernate.event.spi.EventType;
import org.hibernate.event.spi.PostCollectionRemoveEvent;
import org.hibernate.event.spi.PostCollectionRemoveEventListener;
import org.hibernate.event.spi.PreCollectionRemoveEvent;
import org.hibernate.event.spi.PreCollectionRemoveEventListener;
import org.hibernate.persister.collection.CollectionPersister;
/**
* The action for removing a collection
*/
public final class CollectionRemoveAction extends CollectionAction {
private final Object affectedOwner;
private boolean emptySnapshot;
/**
* Removes a persistent collection from its loaded owner.
*
* Use this constructor when the collection is non-null.
*
* @param collection The collection to to remove; must be non-null
* @param persister The collection's persister
* @param id The collection key
* @param emptySnapshot Indicates if the snapshot is empty
* @param session The session
*
* @throws AssertionFailure if collection is null.
*/
public CollectionRemoveAction(
final PersistentCollection collection,
final CollectionPersister persister,
final Serializable id,
final boolean emptySnapshot,
final SessionImplementor session) {
super( persister, collection, id, session );
if ( collection == null ) {
throw new AssertionFailure("collection == null");
}
this.emptySnapshot = emptySnapshot;
// the loaded owner will be set to null after the collection is removed,
// so capture its value as the affected owner so it is accessible to
// both pre- and post- events
this.affectedOwner = session.getPersistenceContext().getLoadedCollectionOwnerOrNull( collection );
}
/**
* Removes a persistent collection from a specified owner.
*
* Use this constructor when the collection to be removed has not been loaded.
*
* @param affectedOwner The collection's owner; must be non-null
* @param persister The collection's persister
* @param id The collection key
* @param emptySnapshot Indicates if the snapshot is empty
* @param session The session
*
* @throws AssertionFailure if affectedOwner is null.
*/
public CollectionRemoveAction(
final Object affectedOwner,
final CollectionPersister persister,
final Serializable id,
final boolean emptySnapshot,
final SessionImplementor session) {
super( persister, null, id, session );
if ( affectedOwner == null ) {
throw new AssertionFailure("affectedOwner == null");
}
this.emptySnapshot = emptySnapshot;
this.affectedOwner = affectedOwner;
}
@Override
public void execute() throws HibernateException {
preRemove();
if ( !emptySnapshot ) {
// an existing collection that was either non-empty or uninitialized
// is replaced by null or a different collection
// (if the collection is uninitialized, hibernate has no way of
// knowing if the collection is actually empty without querying the db)
getPersister().remove( getKey(), getSession() );
}
final PersistentCollection collection = getCollection();
if ( collection != null ) {
getSession().getPersistenceContext().getCollectionEntry( collection ).afterAction( collection );
}
evict();
postRemove();
if ( getSession().getFactory().getStatistics().isStatisticsEnabled() ) {
getSession().getFactory().getStatisticsImplementor().removeCollection( getPersister().getRole() );
}
}
private void preRemove() {
final EventListenerGroup<PreCollectionRemoveEventListener> listenerGroup = listenerGroup( EventType.PRE_COLLECTION_REMOVE );
if ( listenerGroup.isEmpty() ) {
return;
}
final PreCollectionRemoveEvent event = new PreCollectionRemoveEvent(
getPersister(),
getCollection(),
eventSource(),
affectedOwner
);
for ( PreCollectionRemoveEventListener listener : listenerGroup.listeners() ) {
listener.onPreRemoveCollection( event );
}
}
private void postRemove() {
final EventListenerGroup<PostCollectionRemoveEventListener> listenerGroup = listenerGroup( EventType.POST_COLLECTION_REMOVE );
if ( listenerGroup.isEmpty() ) {
return;
}
final PostCollectionRemoveEvent event = new PostCollectionRemoveEvent(
getPersister(),
getCollection(),
eventSource(),
affectedOwner
);
for ( PostCollectionRemoveEventListener listener : listenerGroup.listeners() ) {
listener.onPostRemoveCollection( event );
}
}
}