hibernateutil.java

《基于Eclipse的开源框架技术与实战》[第8章]随书源码

package com.free.hibernate.util;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

/**
 * <p>Title: Eclipse Plugin Development</p>
 * <p>Description: Free download</p>
 * <p>Copyright: Copyright (c) 2006</p>
 * <p>Company: Free</p>
 * @author gan.shu.man
 * @version 1.0
 */

public class HibernateUtil {

	public static SessionFactory sessionFactory;

	public static final ThreadLocal session = new ThreadLocal();

	/**
	 * 创建SessionFactory对象
	 */
	public static void buildSessionFactory() {
		try {
			// 从hibernate.cfg.xml创建SessionFactory
			sessionFactory = new Configuration().configure()
					.buildSessionFactory();
		} catch (Throwable ex) {
			System.err.println("Initial SessionFactory creation failed." + ex);
			throw new ExceptionInInitializerError(ex);
		}
	}

	/**
	 * 从SessionFactory
	 */
	public static Session currentSession() throws HibernateException {
		// 从ThreadLocal取出Session对象
		Session s = (Session) session.get();
		// 如果ThreadLocal中Session对象为空，则创建Session
		if (s == null) {
			s = sessionFactory.openSession();
			// 把Session保存，做为ThreadLocal的变量副本
			session.set(s);
		}
		return s;
	}

}