Hibernate学习笔记1--------一个简单的应用

工具类--------->

/***用单例模式读取配置文件，并返回SessionFactory和Session*/package com.xx.utils;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;public final class HibernateUtil {private HibernateUtil(){};private static SessionFactory sf;private static Session s;static{Configuration cfg = new Configuration();cfg.configure();sf = cfg.buildSessionFactory();}public static SessionFactory getSessionFactory() {return sf;}public static Session getSession() {return sf.openSession();}}  

 

接口--------------------------->

/** * CURD接口 */package com.xx.Dao;import com.xx.hibernate.User;public interface UserDao {public void saveUser(User user);public User findUserById(int id);public User findUserByName(String name);public void updateUser(User user);public void remove(User user);}

 

接口实现-------------------->

package com.itcast.Dao.impl;import org.hibernate.Session;import org.hibernate.Transaction;import com.itcast.Dao.UserDao;import com.itcast.hibernate.User;import com.itcast.utils.HibernateUtil;public class UserDaoImpl implements UserDao {public User findUserById(int id) {User user = null;Session s = null;try{ s = HibernateUtil.getSession(); user = (User)s.get(User.class, id);}finally{if(s != null)s.close();}return user;}public User findUserByName(String name) {User user = null;Session s = null;try{ s = HibernateUtil.getSession(); user = (User)s.createQuery("from User o where o.name =?") .setParameter(0, name).uniqueResult();}finally{if(s != null)s.close();}return user;}public void remove(User user) {Session s = null;try{ s = HibernateUtil.getSession(); Transaction tx = s.beginTransaction(); s.delete(user); tx.commit();}finally{if(s != null)s.close();}}public void saveUser(User user) {Session s = null;try{ s = HibernateUtil.getSession(); Transaction tx = s.beginTransaction(); s.save(user); tx.commit();}finally{if(s != null)s.close();}}public void updateUser(User user) {Session s = null;try{ s = HibernateUtil.getSession(); Transaction tx = s.beginTransaction(); s.update(user); tx.commit();}finally{if(s != null)s.close();}}}