001 /*
002 GRANITE DATA SERVICES
003 Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004
005 This file is part of Granite Data Services.
006
007 Granite Data Services is free software; you can redistribute it and/or modify
008 it under the terms of the GNU Library General Public License as published by
009 the Free Software Foundation; either version 2 of the License, or (at your
010 option) any later version.
011
012 Granite Data Services is distributed in the hope that it will be useful, but
013 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015 for more details.
016
017 You should have received a copy of the GNU Library General Public License
018 along with this library; if not, see <http://www.gnu.org/licenses/>.
019 */
020
021 package org.granite.tide.seam.lazy;
022
023 import java.io.Serializable;
024
025 import javax.persistence.EntityManager;
026 import javax.persistence.Query;
027
028 import org.granite.context.GraniteContext;
029 import org.granite.messaging.amf.io.util.ClassGetter;
030 import org.granite.tide.TidePersistenceManager;
031 import org.jboss.seam.Entity;
032 import org.jboss.seam.util.Reflections;
033
034 /**
035 * Manager responsible for the maintaining a refernce for the PersistenceContext(JPA).
036 * @author CIngram
037 */
038 public class PersistenceContextManager implements TidePersistenceManager {
039
040 private EntityManager em;
041
042 public PersistenceContextManager() {
043 }
044
045 public PersistenceContextManager(EntityManager em) {
046 this.em = em;
047 }
048
049 /**
050 * Attach the passed in entity with the EntityManager.
051 * @param entity
052 * @return the attached entity object
053 */
054 public Object attachEntity(Object entity, String[] propertyNames) {
055 Object attachedEntity = null;
056 ClassGetter getter = GraniteContext.getCurrentInstance().getGraniteConfig().getClassGetter();
057
058 //the get is called to give the children a chance to override and
059 //use the implemented method
060 attachedEntity = fetchEntity(entity, propertyNames);
061
062 if (attachedEntity != null && propertyNames != null) {
063 for (int i = 0; i < propertyNames.length; i++) {
064 try {
065 Object initializedObj = Reflections.getGetterMethod(attachedEntity.getClass(), propertyNames[i]).invoke(attachedEntity);
066
067 //This is here to make sure the list is forced to return a value while operating inside of a
068 //session. Forcing the initialization of object.
069 if (getter != null)
070 getter.initialize(entity, propertyNames[i], initializedObj);
071 }
072 catch (Exception e) {
073 throw new RuntimeException("Could not initialize entity " + attachedEntity, e);
074 }
075 }
076 }
077
078 return attachedEntity;
079 }
080
081 /**
082 * attaches the entity to the JPA context.
083 * @return the attached entity
084 */
085 public Object fetchEntity(Object entity, String[] fetch) {
086 Serializable id = (Serializable)Entity.forClass(entity.getClass()).getIdentifier(entity);
087 if (id == null)
088 return null;
089
090 if (fetch == null || em.getDelegate().getClass().getName().indexOf(".hibernate.") < 0)
091 return em.find(entity.getClass(), id);
092
093 for (String f : fetch) {
094 Query q = em.createQuery("select e from " + entity.getClass().getName() + " e left join fetch e." + f + " where e = :entity");
095 q.setParameter("entity", entity);
096 entity = q.getSingleResult();
097 }
098 return entity;
099 }
100 }