Hibernate4UnitOfWork.java

/*
 * Copyright 2005 The Apache Software Foundation.
 *
 * 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 net.sf.beanlib.hibernate4;

import org.apache.log4j.Logger;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

/**
 * Hibernate 4 Unit Of Work. A Hibernate Unit-Of-Work means a unit of work that executes within a single atomic
 * Hibernate transaction that either commits or roll backs upon returning from the execution.
 * 
 * @author Joe D. Velopar
 */
public abstract class Hibernate4UnitOfWork {
    private static final Logger logger = Logger.getLogger(Hibernate4UnitOfWork.class);

    protected final Session session;

    public Hibernate4UnitOfWork(Session sess) {
        this.session = sess;
    }

    /**
     * Executes a unit of work within a Hibernate transaction.
     */
    public final void execute() throws HibernateException {
        Transaction tx = session.beginTransaction();

        logger.info("execute() - beginTransaction");
        try {
            doit();
            tx.commit();
            logger.info("execute() - tx.commit");
            tx = null;
        } finally {
            if (tx != null) {
                tx.rollback();
                logger.info("execute() - tx.rollback");
            }
        }
    }

    /**
     * Method that a subclass overrides to provide the actual work to be done within a Hibernate transaction.
     */
    protected abstract void doit() throws HibernateException;
}