Struts2+hibernate 源码

package org.yeeku.tools; import org.hibernate.*; import org.hibernate.cfg.*; /** * @author yeeku.H.lee kongyeeku@163.com * @version 1.0 * <br>Copyright (C), 2005-2008, yeeku.H.Lee * <br>This program is protected by copyright laws. * <br>Program Name: * <br>Date: */ public class HibernateUtil { public static final SessionFactory sessionFactory; static { try { //采用默认的hibernate.cfg.xml来启动一个Configuration的实例 Configuration configuration=new Configuration().configure(); //由Configuration的实例来创建一个SessionFactory实例 sessionFactory = configuration.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); } } //ThreadLocal并不是线程本地化的实现,而是线程局部变量。也就是说每个使用该变量的线程都必须为 //该变量提供一个副本,每个线程改变该变量的值仅仅是改变该副本的值,而不会影响其他线程的该变量 //的值. //ThreadLocal是隔离多个线程的数据共享，不存在多个线程之间共享资源,因此不再需要对线程同步 public static final ThreadLocal session = new ThreadLocal(); public static Session currentSession() throws HibernateException { Session s = (Session) session.get(); //如果该线程还没有Session,则创建一个新的Session if (s == null) { s = sessionFactory.openSession(); //将获得的Session变量存储在ThreadLocal变量session里 session.set(s); } return s; } public static void closeSession() throws HibernateException { Session s = (Session) session.get(); if (s != null) s.close(); session.set(null); } }