HibernateUtil工具类在hibernate3下与hibernate4下的区别

以前一直在用Hibernate3 做应用系统，包括目前很多应用程序都是基于Hibernate3 写的，不过 Hibernate 4 都出来好久了，今天下载Hibernate 4.3 Final 版本，下来玩了一下, 发现 得到 sessionFactory 的方法过失了，虽然还是能用，但总感觉不爽. 所以看了下怎么写Hibernate4下的 Util类

Hibernate 3的 HibernateUtil

package com.yihaomen.hibernate.util;

import org.hibernate.SessionFactory;
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
            return new Configuration().configure().buildSessionFactory();
        }
        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;
    }
    
    public static void shutdown() {
    	getSessionFactory().close();
    }

}

然而 return new Configuration().configure().buildSessionFactory(); 这句话已经过期了，于是在网上查找了一下，原来在 Hibernate4 中要这样做.

package com.yihaomen.hibernate.util;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
public class HibernateUtil
{
	private static final SessionFactory sessionFactory;
	static
	{
		try
		{
			Configuration cfg = new Configuration().configure();
			ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(cfg.getProperties()).build();

			sessionFactory = cfg.buildSessionFactory(serviceRegistry);
		}
		catch (Throwable e)
		{
			throw new ExceptionInInitializerError(e);
		}
	}

	private HibernateUtil()
	{
	}

	public static SessionFactory getSessionFactory()
	{
		return sessionFactory;
	}

}

但是，同样发现出了问题，org.hibernate.service.ServiceRegistryBuilder 已经 deprecated 了，所以这还不是最终的方法，于是在hibernate 官方去搜索，发现了如下答案:

Class ServiceRegistryBuilder

java.lang.Object
org.hibernate.boot.registry.StandardServiceRegistryBuilder
org.hibernate.service.ServiceRegistryBuilder
Deprecated. 
Use StandardServiceRegistryBuilder instead

@Deprecated
public class ServiceRegistryBuilder
extends StandardServiceRegistryBuilder

看到标粗体的部分了吗，这就是重点, 需要用 StandardServiceRegistryBuilder 代替 ServiceRegistryBuilder 这个类。

hibernate4 HibernateUtil

package com.yihaomen.hibernate.util;

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

public class HibernateUtil
{
	private static final SessionFactory sessionFactory;
	static
	{
		try
		{
			Configuration cfg = new Configuration().configure();
			ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(cfg.getProperties()).build();

			sessionFactory = cfg.buildSessionFactory(serviceRegistry);
		}
		catch (Throwable e)
		{
			throw new ExceptionInInitializerError(e);
		}
	}

	private HibernateUtil()
	{
	}

	public static SessionFactory getSessionFactory()
	{
		return sessionFactory;
	}

}

以上就是HIbernate4 的 Util 工具的一个基本演变过程.Use StandardServiceRegistryBuilder instead

From：一号门