/*
 * Copyright 2015 JBoss Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * 
 *      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.jbpm.process.audit.strategy;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;

public class SpringStandaloneLocalSharedEntityManagerStrategy implements PersistenceStrategy {

    private EntityManager em;
    private boolean manageTx;
    
    public SpringStandaloneLocalSharedEntityManagerStrategy(EntityManagerFactory emf) {
       this.em = emf.createEntityManager();
       this.manageTx = true;
    }

    public SpringStandaloneLocalSharedEntityManagerStrategy(EntityManager em) {
       this.em = em;
       this.manageTx = false;
    }

    @Override
    public EntityManager getEntityManager() {
        return this.em;
    }

    @Override
    public Object joinTransaction(EntityManager em) {
        if (manageTx) {
        	em.getTransaction().begin();
        }
        return manageTx;
    }

    @Override
    public void leaveTransaction(EntityManager em, Object transaction) {
        if (manageTx) {
        	em.getTransaction().commit();
        }
    }

    @Override
    public void dispose() {
        // do nothing, because the em is SHARED.. 
        em = null;
    }

}
