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
021package org.granite.tide.seam.lazy;
022
023import java.io.Serializable;
024
025import javax.persistence.EntityManager;
026import javax.persistence.Query;
027
028import org.jboss.seam.Component;
029import org.jboss.seam.Entity;
030import org.jboss.seam.framework.PersistenceController;
031
032
033/**
034 * Manager responsible for looking up the EntityHome from the Seam context.
035 * @author cingram
036 *
037 */
038public class PersistenceControllerManager extends PersistenceContextManager {
039    
040    private String controllerName;  
041
042    public PersistenceControllerManager(String controllerName) {
043        this.controllerName = controllerName;
044    }
045    
046    /**
047     * Attach the passed in entity with the EntityManager stored 
048     * in the EntityHome object.
049     * @param entity
050     * @return the attached hibernate object
051     */
052    @Override
053    public Object fetchEntity(Object entity, String[] fetch) {
054        PersistenceController<?> controller = (PersistenceController<?>)Component.getInstance(controllerName);
055        EntityManager em = (EntityManager)controller.getPersistenceContext();
056        Serializable id = (Serializable)Entity.forClass(entity.getClass()).getIdentifier(entity);
057        if (id == null)
058            return null;
059        
060        if (fetch == null || em.getDelegate().getClass().getName().indexOf(".hibernate.") < 0)
061                return em.find(entity.getClass(), id);
062        
063        for (String f : fetch) {
064                Query q = em.createQuery("select e from " + entity.getClass().getName() + " e left join fetch e." + f + " where e = :entity");
065                q.setParameter("entity", entity);
066                entity = q.getSingleResult();
067        }
068        return entity;
069    }
070
071}