/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 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.envers.event;
import java.io.Serializable;
import java.util.Set;
import org.hibernate.engine.spi.SessionImplementor;
import org.hibernate.envers.configuration.AuditConfiguration;
import org.hibernate.envers.entities.RelationDescription;
import org.hibernate.envers.entities.RelationType;
import org.hibernate.envers.entities.mapper.id.IdMapper;
import org.hibernate.envers.synchronization.AuditProcess;
import org.hibernate.envers.synchronization.work.CollectionChangeWorkUnit;
import org.hibernate.envers.tools.Tools;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.proxy.HibernateProxy;
/**
* Base class for all Envers event listeners
*
* @author Adam Warski (adam at warski dot org)
* @author HernпїЅn Chanfreau
* @author Steve Ebersole
* @author Michal Skowronek (mskowr at o2 dot pl)
*/
public abstract class BaseEnversEventListener implements EnversListener {
private AuditConfiguration enversConfiguration;
protected BaseEnversEventListener(AuditConfiguration enversConfiguration) {
this.enversConfiguration = enversConfiguration;
}
@Override
public AuditConfiguration getAuditConfiguration() {
return enversConfiguration;
}
protected final void generateBidirectionalCollectionChangeWorkUnits(
AuditProcess auditProcess,
EntityPersister entityPersister,
String entityName,
Object[] newState,
Object[] oldState,
SessionImplementor session) {
// Checking if this is enabled in configuration ...
if ( ! enversConfiguration.getGlobalCfg().isGenerateRevisionsForCollections() ) {
return;
}
// Checks every property of the entity, if it is an "owned" to-one relation to another entity.
// If the value of that property changed, and the relation is bi-directional, a new revision
// for the related entity is generated.
String[] propertyNames = entityPersister.getPropertyNames();
for ( int i=0; i<propertyNames.length; i++ ) {
String propertyName = propertyNames[i];
RelationDescription relDesc = enversConfiguration.getEntCfg().getRelationDescription(entityName, propertyName);
if (relDesc != null && relDesc.isBidirectional() && relDesc.getRelationType() == RelationType.TO_ONE &&
relDesc.isInsertable()) {
// Checking for changes
Object oldValue = oldState == null ? null : oldState[i];
Object newValue = newState == null ? null : newState[i];
if (!Tools.entitiesEqual( session, relDesc.getToEntityName(), oldValue, newValue )) {
// We have to generate changes both in the old collection (size decreses) and new collection
// (size increases).
if (newValue != null) {
addCollectionChangeWorkUnit(auditProcess, session, entityName, relDesc, newValue);
}
if (oldValue != null) {
addCollectionChangeWorkUnit(auditProcess, session, entityName, relDesc, oldValue);
}
}
}
}
}
private void addCollectionChangeWorkUnit(AuditProcess auditProcess, SessionImplementor session,
String fromEntityName, RelationDescription relDesc, Object value) {
// relDesc.getToEntityName() doesn't always return the entity name of the value - in case
// of subclasses, this will be root class, no the actual class. So it can't be used here.
String toEntityName;
Serializable id;
if (value instanceof HibernateProxy) {
HibernateProxy hibernateProxy = (HibernateProxy) value;
toEntityName = session.bestGuessEntityName(value);
id = hibernateProxy.getHibernateLazyInitializer().getIdentifier();
// We've got to initialize the object from the proxy to later read its state.
value = Tools.getTargetFromProxy(session.getFactory(), hibernateProxy);
} else {
toEntityName = session.guessEntityName(value);
IdMapper idMapper = enversConfiguration.getEntCfg().get(toEntityName).getIdMapper();
id = (Serializable) idMapper.mapToIdFromEntity(value);
}
Set<String> toPropertyNames = enversConfiguration.getEntCfg()
.getToPropertyNames(fromEntityName, relDesc.getFromPropertyName(), toEntityName);
String toPropertyName = toPropertyNames.iterator().next();
auditProcess.addWorkUnit(new CollectionChangeWorkUnit(session, toEntityName,
toPropertyName, enversConfiguration, id, value));
}
}