官方文档提供的HibernateUtil是这样的

package org.hibernate.tutorial.util;

import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {

    private static final SessionFactory sessionFactory = buildSessionFactory();

    private static SessionFactory buildSessionFactory() {
        try {
            // Create the SessionFactory from hibernate.cfg.xml
            //明显有语法错误，我在下面加了一句return
            new Configuration().configure().buildSessionFactory(
			    new StandardServiceRegistryBuilder().build() );
        }
        catch (Throwable ex) {
            // Make sure you log the exception, as it might be swallowed
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }

}

用这个报Access to DialectResolutionInfo cannot be null when “”hibernate.dialect”” not这个错误，然后在网上找到的解决方案改成下面这样，就没问题了

package com.example.util;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;

public class HibernateUtil {

    private static final SessionFactory sessionFactory = buildSessionFactory();

    private static SessionFactory buildSessionFactory() {
        try {
            // Create the SessionFactory from hibernate.cfg.xml
        
        	Configuration cfg = new Configuration().configure();
        	ServiceRegistry serviceRegistry= new ServiceRegistryBuilder().applySettings(cfg.getProperties()).buildServiceRegistry();
        	return cfg.buildSessionFactory(serviceRegistry);
//           return  new Configuration().configure().buildSessionFactory(
//			    new StandardServiceRegistryBuilder().build() );
        }
        catch (Throwable ex) {
            // Make sure you log the exception, as it might be swallowed
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }

}

到底是信官方的还是…..还有后面那个方法报了好几个deprecated的警告
初学真是越学越奇怪啊。。