package com.crystal.hibernate;

import javax.naming.InitialContext;
import org.apache.log4j.Logger;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.cfg.Environment;


public class InitSessionFactory
{

    private InitSessionFactory()
    {
    }

    private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";

    private static final Configuration cfg = new Configuration();

    private static org.hibernate.SessionFactory sessionFactory;

    public static SessionFactory getInstance()
    {
        if (sessionFactory == null) {
            initSessionFactory();
        }
        return sessionFactory;
    }

    public Session openSession()
    {
        return sessionFactory.getCurrentSession();
    }

    public Session getCurrentSession()
    {
        return sessionFactory.getCurrentSession();
    }

    private static synchronized void initSessionFactory()
    {

        Logger log = Logger.getLogger(InitSessionFactory.class);
        if (sessionFactory == null) {


            try {
                cfg.configure(CONFIG_FILE_LOCATION);
                String sessionFactoryJndiName = cfg
                    .getProperty(Environment.SESSION_FACTORY_NAME);
                if (sessionFactoryJndiName != null) {
                    cfg.buildSessionFactory();
                    log.debug("get a jndi session factory");
                    sessionFactory = (SessionFactory) (new InitialContext())
                        .lookup(sessionFactoryJndiName);
                }
                else {
                    log.debug("classic factory");
                    sessionFactory = cfg.buildSessionFactory();
                }

            }
            catch (Exception e) {
                System.err
                    .println("%%%% Error Creating HibernateSessionFactory %%%%");
                e.printStackTrace();
                throw new HibernateException(
                    "Could not initialize the Hibernate configuration");
            }
        }
    }

    public static void close()
    {
        if (sessionFactory != null) {
            sessionFactory.close();
        }
        sessionFactory = null;

    }
}