HibernateUtil工具类的使用

为了简化代码的重复性，使用HibernateUtil工具类对Hibernate有关的代码进行整合

主要实现有，getSessionFactory()，getSession()，closeSession()

public class HibernateUtil {

	  private static final SessionFactory sessionFactory=buildSessionFactory();
	  private static  Session session;
	  

	private static SessionFactory buildSessionFactory(){
		Configuration configuration=new Configuration().configure(); //实例化配置
		ServiceRegistry serviceRegistry=new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();//生成服务登记
	    return configuration.buildSessionFactory(serviceRegistry);
	}
	//获取sessionFactory
	public static SessionFactory getSessionFactory(){
		return sessionFactory;
	}
	//获取session
	public static Session getSession(){
		return sessionFactory.openSession();
	}
	//关闭session
	public static void closeSession(){
		if(session!=null){
			session.close();
		}
	}
}