/**
 * The MIT License
 * Copyright (c) 2014 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.cqrs.util;

import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * This class simply returns one instance of {@link SessionFactory} initialized when the application is started
 *
 */
public class HibernateUtil {

  private static final SessionFactory SESSIONFACTORY = buildSessionFactory();
  private static final Logger LOGGER = LoggerFactory.getLogger(HibernateUtil.class);

  private static SessionFactory buildSessionFactory() {

    // configures settings from hibernate.cfg.xml
    final StandardServiceRegistry registry = new StandardServiceRegistryBuilder().configure().build();
    try {
      return new MetadataSources(registry).buildMetadata().buildSessionFactory();
    } catch (Exception ex) {
      StandardServiceRegistryBuilder.destroy(registry);
      LOGGER.error("Initial SessionFactory creation failed." + ex);
      throw new ExceptionInInitializerError(ex);
    }
  }

  public static SessionFactory getSessionFactory() {
    return SESSIONFACTORY;
  }

}
