001/**
002 *   GRANITE DATA SERVICES
003 *   Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004 *
005 *   This file is part of the Granite Data Services Platform.
006 *
007 *   Granite Data Services is free software; you can redistribute it and/or
008 *   modify it under the terms of the GNU Lesser General Public
009 *   License as published by the Free Software Foundation; either
010 *   version 2.1 of the License, or (at your option) any later version.
011 *
012 *   Granite Data Services is distributed in the hope that it will be useful,
013 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
014 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015 *   General Public License for more details.
016 *
017 *   You should have received a copy of the GNU Lesser General Public
018 *   License along with this library; if not, write to the Free Software
019 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020 *   USA, or see <http://www.gnu.org/licenses/>.
021 */
022package org.granite.tide.data;
023
024import java.io.Serializable;
025import java.util.List;
026
027import javax.persistence.*;
028
029import org.granite.logging.Logger;
030import org.granite.tide.TideTransactionManager;
031
032
033/**
034 * Responsible for attaching a entity with the entity mangager
035 * @author cingram
036 *
037 */
038public class JPAPersistenceManager extends AbstractTidePersistenceManager implements TideTransactionPersistenceManager {
039        
040        private static final Logger log = Logger.getLogger(JPAPersistenceManager.class);
041        
042        protected EntityManager entityManager;
043        protected EntityManagerFactory entityManagerFactory;
044        protected boolean shouldCloseEntityManager = false;
045
046        
047        public JPAPersistenceManager(TideTransactionManager tm) {
048                super(tm);
049        }
050
051        public JPAPersistenceManager(EntityManager em) {
052                this(em, null);
053        }
054        
055        public JPAPersistenceManager(EntityManager em, TideTransactionManager tm) {
056                super(tm != null ? tm : new JPATransactionManager());
057                
058        if (em == null)
059                throw new RuntimeException("entity manager cannot be null");
060        
061        this.entityManager =  em;
062        }
063        
064        public JPAPersistenceManager(EntityManagerFactory emf) {
065                this(emf, null);
066        }
067        
068        public JPAPersistenceManager(EntityManagerFactory emf, TideTransactionManager tm) {
069                super(tm != null ? tm : new JPATransactionManager());
070                
071        if (emf == null)
072                throw new RuntimeException("entity manager factory cannot be null");
073        
074        this.entityManagerFactory = emf;
075        }
076        
077        public Object getCurrentTransaction() {
078                initEntityManager();
079            EntityTransaction et = entityManager.getTransaction();   // Try to get a local resource transaction
080            et.begin();
081            return et;
082        }
083        
084        protected void initEntityManager() {
085                if (this.entityManager != null)
086                        return;
087        this.entityManager = entityManagerFactory.createEntityManager();
088        shouldCloseEntityManager = true;
089        }
090        
091        @Override
092        public void close() {
093                if (shouldCloseEntityManager && this.entityManager != null)
094                        this.entityManager.close();
095        }
096        
097        
098    /**
099     * Finds the entity with the JPA context.
100     * @return the entity with the JPA context.
101     */
102        @Override
103        public Object fetchEntity(Object entity, String[] fetch) {
104                org.granite.util.Entity tideEntity = new org.granite.util.Entity(entity);
105                Serializable id = (Serializable)tideEntity.getIdentifier();
106                
107        if (id == null)
108            return null;
109        
110        initEntityManager();
111        
112        if (fetch == null || entityManager.getDelegate().getClass().getName().indexOf(".hibernate.") < 0)
113                return entityManager.find(entity.getClass(), id);
114        
115        for (String f : fetch) {
116                Query q = entityManager.createQuery("select e from " + entity.getClass().getName() + " e left join fetch e." + f + " where e = :entity");
117                q.setParameter("entity", entity);
118                List<?> results = q.getResultList();
119                if (!results.isEmpty())
120                        entity = results.get(0);
121                else
122                        log.warn("Could not find entity %s to initialize, id: %s", entity.getClass().getName(), id);  
123        }
124        return entity;
125        }
126
127}