/*
* Copyright 2002-2014 the original author or authors.
*
* Licensed 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.springframework.orm.jpa.vendor;
import java.sql.Connection;
import java.sql.SQLException;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceException;
import org.apache.commons.logging.LogFactory;
import org.apache.openjpa.persistence.FetchPlan;
import org.apache.openjpa.persistence.OpenJPAEntityManager;
import org.apache.openjpa.persistence.OpenJPAPersistence;
import org.apache.openjpa.persistence.jdbc.IsolationLevel;
import org.apache.openjpa.persistence.jdbc.JDBCFetchPlan;
import org.springframework.jdbc.datasource.ConnectionHandle;
import org.springframework.jdbc.datasource.ConnectionHolder;
import org.springframework.jdbc.support.JdbcUtils;
import org.springframework.orm.jpa.DefaultJpaDialect;
import org.springframework.transaction.SavepointManager;
import org.springframework.transaction.TransactionDefinition;
import org.springframework.transaction.TransactionException;
/**
* {@link org.springframework.orm.jpa.JpaDialect} implementation for Apache OpenJPA.
* Developed and tested against OpenJPA 2.2.
*
* @author Juergen Hoeller
* @author Costin Leau
* @since 2.0
*/
@SuppressWarnings("serial")
public class OpenJpaDialect extends DefaultJpaDialect {
@Override
public Object beginTransaction(EntityManager entityManager, TransactionDefinition definition)
throws PersistenceException, SQLException, TransactionException {
OpenJPAEntityManager openJpaEntityManager = getOpenJPAEntityManager(entityManager);
if (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT) {
// Pass custom isolation level on to OpenJPA's JDBCFetchPlan configuration
FetchPlan fetchPlan = openJpaEntityManager.getFetchPlan();
if (fetchPlan instanceof JDBCFetchPlan) {
IsolationLevel isolation = IsolationLevel.fromConnectionConstant(definition.getIsolationLevel());
((JDBCFetchPlan) fetchPlan).setIsolation(isolation);
}
}
entityManager.getTransaction().begin();
if (!definition.isReadOnly()) {
// Like with EclipseLink, make sure to start the logic transaction early so that other
// participants using the connection (such as JdbcTemplate) run in a transaction.
openJpaEntityManager.beginStore();
}
// Custom implementation for OpenJPA savepoint handling
return new OpenJpaTransactionData(openJpaEntityManager);
}
@Override
public ConnectionHandle getJdbcConnection(EntityManager entityManager, boolean readOnly)
throws PersistenceException, SQLException {
return new OpenJpaConnectionHandle(getOpenJPAEntityManager(entityManager));
}
/**
* Return the OpenJPA-specific variant of {@code EntityManager}.
* @param em the generic {@code EntityManager} instance
* @return the OpenJPA-specific variant of {@code EntityManager}
*/
protected OpenJPAEntityManager getOpenJPAEntityManager(EntityManager em) {
return OpenJPAPersistence.cast(em);
}
/**
* Transaction data Object exposed from {@code beginTransaction},
* implementing the {@link SavepointManager} interface.
*/
private static class OpenJpaTransactionData implements SavepointManager {
private final OpenJPAEntityManager entityManager;
private int savepointCounter = 0;
public OpenJpaTransactionData(OpenJPAEntityManager entityManager) {
this.entityManager = entityManager;
}
@Override
public Object createSavepoint() throws TransactionException {
this.savepointCounter++;
String savepointName = ConnectionHolder.SAVEPOINT_NAME_PREFIX + this.savepointCounter;
this.entityManager.setSavepoint(savepointName);
return savepointName;
}
@Override
public void rollbackToSavepoint(Object savepoint) throws TransactionException {
this.entityManager.rollbackToSavepoint((String) savepoint);
}
@Override
public void releaseSavepoint(Object savepoint) throws TransactionException {
try {
this.entityManager.releaseSavepoint((String) savepoint);
}
catch (Throwable ex) {
LogFactory.getLog(OpenJpaTransactionData.class).debug(
"Could not explicitly release OpenJPA savepoint", ex);
}
}
}
/**
* {@link ConnectionHandle} implementation that fetches a new OpenJPA-provided
* Connection for every {@code getConnection} call and closes the Connection on
* {@code releaseConnection}. This is necessary because OpenJPA requires the
* fetched Connection to be closed before continuing EntityManager work.
* @see org.apache.openjpa.persistence.OpenJPAEntityManager#getConnection()
*/
private static class OpenJpaConnectionHandle implements ConnectionHandle {
private final OpenJPAEntityManager entityManager;
public OpenJpaConnectionHandle(OpenJPAEntityManager entityManager) {
this.entityManager = entityManager;
}
@Override
public Connection getConnection() {
return (Connection) this.entityManager.getConnection();
}
@Override
public void releaseConnection(Connection con) {
JdbcUtils.closeConnection(con);
}
}
}