/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.ode.dao.jpa;
import javax.persistence.EntityManager;
import javax.transaction.Status;
import javax.transaction.Synchronization;
import javax.transaction.SystemException;
import javax.transaction.TransactionManager;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.ode.dao.DAOConnection;
public class JpaConnection implements DAOConnection {
private static final Log __log = LogFactory.getLog(JpaConnection.class);
final protected EntityManager _em;
final protected TransactionManager _mgr;
final protected JpaTxContext _txCtx;
final protected JpaOperator _operator;
public JpaConnection(EntityManager em, TransactionManager mgr, JpaOperator operator) {
_em = em;
_mgr = mgr;
if (mgr != null) {
_txCtx = new JpaJtaContext();
} else {
_txCtx = new JpaNonTxContext();
}
_operator = operator;
}
public EntityManager getEntityManager() {
return _em;
}
public JpaOperator getJPADaoOperator() {
return _operator;
}
public void close() {
}
public boolean isClosed() {
return _em == null ? true : !_em.isOpen();
}
/** Clear out the entity manager after a commit so no stale entites are
* preserved across transactions and all JPA operations pull data directly from
* the DB.
*
*/
public void clearOnComplete() {
try {
_mgr.getTransaction().registerSynchronization(new Synchronization() {
public void afterCompletion(int i) {
_em.clear();
if(__log.isDebugEnabled()) {
__log.debug("-------> clear the entity manager");
}
}
public void beforeCompletion() {
}
});
} catch (Exception e) {
__log.error("Error adding commit synchronizer", e);
}
}
protected interface JpaTxContext {
public void begin();
public void commit();
public void rollback();
}
class JpaJtaContext implements JpaTxContext {
/**
* Due to the way ODE re-uses connection on ThreadLocals it could be possible
* for the JPA EntityManager to not be created on the current JTA transaction
* and threfore it must by manually bound to the current transaction.
*/
public void begin() {
try {
if (_mgr.getStatus() == Status.STATUS_ACTIVE) {
_em.joinTransaction();
clearOnComplete();
}
} catch (SystemException se) {
__log.error(se);
}
}
public void commit() {
}
public void rollback() {
try {
if (_mgr.getStatus() == Status.STATUS_ACTIVE) {
_mgr.setRollbackOnly();
}
} catch (Exception ex) {
__log.error("Unable to set rollbackOnly", ex);
}
}
}
class JpaNonTxContext implements JpaTxContext {
public void begin() {
_em.getTransaction().begin();
}
public void commit() {
_em.getTransaction().commit();
_em.clear();
}
public void rollback() {
_em.getTransaction().rollback();
_em.clear();
}
}
}