Java_Web三大框架之Hibernate配置文件（二）

下面介绍一下编写Hibernate的配置文件，使用Hibernate操作数据库。

Oracle 数据库驱动jar包

第一步：创建实体类和实体映射文件

public class User {        PRivate int id;    private String username;    private String passWord;}省略get和set方法

<?xml version="1.0"?><!DOCTYPE hibernate-mapping PUBLIC     "-//Hibernate/Hibernate Mapping DTD 3.0//EN"    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping    package="com.msit.hibernate.entity"><!--User实体，t_user数据库表面名-->    <class name="User" table="t_user">                 <!--自增id-->        <id name="id">            <generator class="increment"/>        </id>        <property name="username" />        <property name="password" />    </class></hibernate-mapping>

<!DOCTYPE hibernate-configuration PUBLIC    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"    "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><hibernate-configuration>    <session-factory name="foo">        <!-- 数据库方言 -->        <property name="dialect">            org.hibernate.dialect.OracleDialect        </property>        <!-- 连接数据库Url -->        <property name="hibernate.connection.url">            jdbc:oracle:thin:@localhost:1521:orcl        </property>        <!-- 连接驱动 -->        <property name="hibernate.connection.driver_class">            oracle.jdbc.driver.OracleDriver        </property>        <!-- 用户名 -->        <property name="hibernate.connection.username">epet</property>        <!-- 密码 -->        <property name="hibernate.connection.password">123456</property>                <!-- 自动创建数据库表格 -->        <property name="hibernate.hbm2ddl.auto">update</property>                <!-- 配置映射信息 -->        <mapping resource="com/msit/hibernate/entity/User.hbm.xml" />            </session-factory></hibernate-configuration>注：<session-factory>    <!--省略其他配置-->    <!--注意配置文件名必须包含其相对于classpath 的全路径-->    <mapping resource="cn/jbit/houserent/entity/User.hbm.xml" /></session-factory>

第三步：抽出HibernateUtil接口

package com.msit.hibernate.HibernateUtil;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;public class HibernateUtil {        private HibernateUtil(){            };        public static SessionFactory SessionFactory = null;        static{        //hibernate初始化        Configuration cf = new Configuration();        cf.configure();        SessionFactory = cf.buildSessionFactory();//DriverManager.getconnection()        //Session session = SessionFactory.openSession();//相当于得到Connection对象    }        public static Session getSession(){                return SessionFactory.openSession();    }        public static void closeSession(Session session){        if(session!=null){            session.clear();        }    }}

第四步：编写测试类：

package com.msit.hibernate.test;import java.sql.DriverManager;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.cfg.Configuration;import com.msit.hibernate.HibernateUtil.HibernateUtil;import com.msit.hibernate.entity.User;public class HibernateTest {    /**     * @param args     */    public static void main(String[] args) {                                //创建用户        User user = new User();        user.setId(1);        user.setUsername("master123456");        user.setPassword("123");                Session session = HibernateUtil.getSession();                //进行事务处理        Transaction Transaction = session.beginTransaction();                try {                        //对数据做保存至数据库            session.update(user);                        //提交事务            Transaction.commit();        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();            //如果出现异常则进行事务回滚            Transaction.rollback();        }    }}