/*
* 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 org.hibernate.HibernateException;
import org.hibernate.TransientObjectException;
import org.hibernate.ReplicationMode;
import org.hibernate.LockMode;
import org.hibernate.engine.Cascade;
import org.hibernate.engine.CascadingAction;
import org.hibernate.engine.EntityKey;
import org.hibernate.engine.Status;
import org.hibernate.event.EventSource;
import org.hibernate.event.ReplicateEvent;
import org.hibernate.event.ReplicateEventListener;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.pretty.MessageHelper;
import org.hibernate.type.Type;
import java.io.Serializable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Defines the default replicate event listener used by Hibernate to replicate
* entities in response to generated replicate events.
*
* @author Steve Ebersole
*/
public class DefaultReplicateEventListener extends AbstractSaveEventListener implements ReplicateEventListener {
private static final Logger log = LoggerFactory.getLogger( DefaultReplicateEventListener.class );
/**
* Handle the given replicate event.
*
* @param event The replicate event to be handled.
*
* @throws TransientObjectException An invalid attempt to replicate a transient entity.
*/
public void onReplicate(ReplicateEvent event) {
final EventSource source = event.getSession();
if ( source.getPersistenceContext().reassociateIfUninitializedProxy( event.getObject() ) ) {
log.trace( "uninitialized proxy passed to replicate()" );
return;
}
Object entity = source.getPersistenceContext().unproxyAndReassociate( event.getObject() );
if ( source.getPersistenceContext().isEntryFor( entity ) ) {
log.trace( "ignoring persistent instance passed to replicate()" );
//hum ... should we cascade anyway? throw an exception? fine like it is?
return;
}
EntityPersister persister = source.getEntityPersister( event.getEntityName(), entity );
// get the id from the object
/*if ( persister.isUnsaved(entity, source) ) {
throw new TransientObjectException("transient instance passed to replicate()");
}*/
Serializable id = persister.getIdentifier( entity, source.getEntityMode() );
if ( id == null ) {
throw new TransientObjectException( "instance with null id passed to replicate()" );
}
final ReplicationMode replicationMode = event.getReplicationMode();
final Object oldVersion;
if ( replicationMode == ReplicationMode.EXCEPTION ) {
//always do an INSERT, and let it fail by constraint violation
oldVersion = null;
}
else {
//what is the version on the database?
oldVersion = persister.getCurrentVersion( id, source );
}
if ( oldVersion != null ) {
if ( log.isTraceEnabled() ) {
log.trace(
"found existing row for " +
MessageHelper.infoString( persister, id, source.getFactory() )
);
}
/// HHH-2378
final Object realOldVersion = persister.isVersioned() ? oldVersion : null;
boolean canReplicate = replicationMode.shouldOverwriteCurrentVersion(
entity,
realOldVersion,
persister.getVersion( entity, source.getEntityMode() ),
persister.getVersionType()
);
if ( canReplicate ) {
//will result in a SQL UPDATE:
performReplication( entity, id, realOldVersion, persister, replicationMode, source );
}
else {
//else do nothing (don't even reassociate object!)
log.trace( "no need to replicate" );
}
//TODO: would it be better to do a refresh from db?
}
else {
// no existing row - do an insert
if ( log.isTraceEnabled() ) {
log.trace(
"no existing row, replicating new instance " +
MessageHelper.infoString( persister, id, source.getFactory() )
);
}
final boolean regenerate = persister.isIdentifierAssignedByInsert(); // prefer re-generation of identity!
final EntityKey key = regenerate ?
null : new EntityKey( id, persister, source.getEntityMode() );
performSaveOrReplicate(
entity,
key,
persister,
regenerate,
replicationMode,
source,
true
);
}
}
protected boolean visitCollectionsBeforeSave(Object entity, Serializable id, Object[] values, Type[] types, EventSource source) {
//TODO: we use two visitors here, inefficient!
OnReplicateVisitor visitor = new OnReplicateVisitor( source, id, entity, false );
visitor.processEntityPropertyValues( values, types );
return super.visitCollectionsBeforeSave( entity, id, values, types, source );
}
protected boolean substituteValuesIfNecessary(
Object entity,
Serializable id,
Object[] values,
EntityPersister persister,
SessionImplementor source) {
return false;
}
protected boolean isVersionIncrementDisabled() {
return true;
}
private void performReplication(
Object entity,
Serializable id,
Object version,
EntityPersister persister,
ReplicationMode replicationMode,
EventSource source) throws HibernateException {
if ( log.isTraceEnabled() ) {
log.trace(
"replicating changes to " +
MessageHelper.infoString( persister, id, source.getFactory() )
);
}
new OnReplicateVisitor( source, id, entity, true ).process( entity, persister );
source.getPersistenceContext().addEntity(
entity,
Status.MANAGED,
null,
new EntityKey( id, persister, source.getEntityMode() ),
version,
LockMode.NONE,
true,
persister,
true,
false
);
cascadeAfterReplicate( entity, persister, replicationMode, source );
}
private void cascadeAfterReplicate(
Object entity,
EntityPersister persister,
ReplicationMode replicationMode,
EventSource source) {
source.getPersistenceContext().incrementCascadeLevel();
try {
new Cascade( CascadingAction.REPLICATE, Cascade.AFTER_UPDATE, source )
.cascade( persister, entity, replicationMode );
}
finally {
source.getPersistenceContext().decrementCascadeLevel();
}
}
protected CascadingAction getCascadeAction() {
return CascadingAction.REPLICATE;
}
}