Spring Framework example source code file (HibernateJpaDialect.java)

This example Spring Framework source code file (HibernateJpaDialect.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

connectionhandle, flushmode, flushmode, hibernateexception, jdbc, object, persistenceexception, persistenceexception, session, session, sessiontransactiondata, sessiontransactiondata, sql, sqlexception, string, transactionexception

The Spring Framework HibernateJpaDialect.java source code

/*
 * Copyright 2002-2007 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.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.ejb.HibernateEntityManager;

import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.datasource.ConnectionHandle;
import org.springframework.jdbc.datasource.SimpleConnectionHandle;
import org.springframework.orm.hibernate3.SessionFactoryUtils;
import org.springframework.orm.jpa.DefaultJpaDialect;
import org.springframework.orm.jpa.EntityManagerFactoryUtils;
import org.springframework.transaction.TransactionDefinition;
import org.springframework.transaction.TransactionException;

/**
 * {@link org.springframework.orm.jpa.JpaDialect} implementation for
 * Hibernate EntityManager. Developed and tested against Hibernate 3.2.
 *
 * @author Costin Leau
 * @author Juergen Hoeller
 * @since 2.0
 */
public class HibernateJpaDialect extends DefaultJpaDialect {

	public Object beginTransaction(EntityManager entityManager, TransactionDefinition definition)
			throws PersistenceException, SQLException, TransactionException {

		super.beginTransaction(entityManager, definition);
		return prepareTransaction(entityManager, definition.isReadOnly(), definition.getName());
	}

	public Object prepareTransaction(EntityManager entityManager, boolean readOnly, String name)
			throws PersistenceException {

		Session session = getSession(entityManager);
		FlushMode flushMode = session.getFlushMode();
		FlushMode previousFlushMode = null;
		if (readOnly) {
			// We should suppress flushing for a read-only transaction.
			session.setFlushMode(FlushMode.MANUAL);
			previousFlushMode = flushMode;
		}
		else {
			// We need AUTO or COMMIT for a non-read-only transaction.
			if (flushMode.lessThan(FlushMode.COMMIT)) {
				session.setFlushMode(FlushMode.AUTO);
				previousFlushMode = flushMode;
			}
		}
		return new SessionTransactionData(session, previousFlushMode);
	}

	public void cleanupTransaction(Object transactionData) {
		((SessionTransactionData) transactionData).resetFlushMode();
	}

	@Override
	public ConnectionHandle getJdbcConnection(EntityManager entityManager, boolean readOnly)
			throws PersistenceException, SQLException {

		Session session = getSession(entityManager);
		Connection con = session.connection();
		return (con != null ? new SimpleConnectionHandle(con) : null);
	}

	public DataAccessException translateExceptionIfPossible(RuntimeException ex) {
		if (ex instanceof HibernateException) {
			return SessionFactoryUtils.convertHibernateAccessException((HibernateException) ex);
		}
		if (ex instanceof PersistenceException && ex.getCause() instanceof HibernateException) {
			return SessionFactoryUtils.convertHibernateAccessException((HibernateException) ex.getCause());
		}
		return EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(ex);
	}

	protected Session getSession(EntityManager em) {
		return ((HibernateEntityManager) em).getSession();
	}


	private static class SessionTransactionData {

		private final Session session;

		private final FlushMode previousFlushMode;

		public SessionTransactionData(Session session, FlushMode previousFlushMode) {
			this.session = session;
			this.previousFlushMode = previousFlushMode;
		}

		public void resetFlushMode() {
			if (this.previousFlushMode != null) {
				this.session.setFlushMode(this.previousFlushMode);
			}
		}
	}

}