hibernate 5.x 创建session方法

public class HibernateSessionFactory {

	private static final ThreadLocal threadLocal = new ThreadLocal();
    private static org.hibernate.SessionFactory sessionFactory;
	
    private static Configuration configuration = new Configuration();
    private static ServiceRegistry serviceRegistry; 

	static {
    	try {
			configuration.configure();
			serviceRegistry = new StandardServiceRegistryBuilder().configure().build();
			try {
				sessionFactory = new MetadataSources(serviceRegistry).buildMetadata().buildSessionFactory();
			} catch (Exception e) {
				StandardServiceRegistryBuilder.destroy(serviceRegistry);
				e.printStackTrace();
			}
		} catch (Exception e) {
			System.err.println("%%%% Error Creating SessionFactory %%%%");
			e.printStackTrace();
		}
    }
    private HibernateSessionFactory() {
    }
	

    public static Session getSession() throws HibernateException {
        Session session = (Session) threadLocal.get();

		if (session == null || !session.isOpen()) {
			if (sessionFactory == null) {
				rebuildSessionFactory();
			}
			session = (sessionFactory != null) ? sessionFactory.openSession()
					: null;
			threadLocal.set(session);
		}

        return session;
    }

	public static void rebuildSessionFactory() {
		try {
			configuration.configure();
			serviceRegistry = new StandardServiceRegistryBuilder().configure().build();
			try {
				sessionFactory = new MetadataSources(serviceRegistry).buildMetadata().buildSessionFactory();
			} catch (Exception e) {
				StandardServiceRegistryBuilder.destroy(serviceRegistry);
				e.printStackTrace();
			}
		} catch (Exception e) {
			System.err.println("%%%% Error Creating SessionFactory %%%%");
			e.printStackTrace();
		}
	}


    public static void closeSession() throws HibernateException {
        Session session = (Session) threadLocal.get();
        threadLocal.set(null);

        if (session != null) {
            session.close();
        }
    }


	public static org.hibernate.SessionFactory getSessionFactory() {
		return sessionFactory;
	}

	public static Configuration getConfiguration() {
		return configuration;
	}

}