上篇博客已经为大家介绍了持久层框架的发展流程，持久层框架的种类。
为了能够使用hibernate快速上手，我们先讲解一个简单的Hibernate应用实例hibernate_first。
1.首先在MyEclipce中新建一个hibernate_first的项目，然后新建后的项目目录为：
2.配置Hibernate环境。
3.编写持久化类User.Java
[java] view plain copy package com.bjpowernode.hibernate; import java.util.Date; public class User { private String id; private String name; private String password; private Date createTime; private Date expireTime; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public Date getCreateTime() { return createTime; } public void setCreateTime(Date createTime) { this.createTime = createTime; } public Date getExpireTime() { return expireTime; } public void setExpireTime(Date expireTime) { this.expireTime = expireTime; } }
4.编写生成映射文件User.hbm.xml。
[java] view plain copy <?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> <class name="com.bjpowernode.hibernate.User"> <id name="id"> <generator class="uuid"/> </id> <property name="name"/> <property name="password"/> <property name="createTime"/> <property name="expireTime"/> </class> </hibernate-mapping>
5.编写hibernate.cfg.xml文件。
[java] view plain copy <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory > <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate_frist</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">root</property> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.show_sql">true</property> <property name="hibernate.format_sql">true</property> <mapping resource="com/bjpowernode/hibernate/User.hbm.xml"/> </session-factory> </hibernate-configuration> 6.生成表的类ExportDB.java。
[java] view plain copy package com.bjpowernode.hibernate; import org.hibernate.cfg.Configuration; import org.hibernate.tool.hbm2ddl.SchemaExport; /** * 将hbm生成ddl * @author Administrator * */ public class ExportDB { public static void main(String[] args) { //默认读取hibernate.cfg.xml文件 Configuration cfg = new Configuration().configure(); SchemaExport export = new SchemaExport(cfg); export.create(true, true); } }
7.以上六个步骤已经把表建起来了下面我们就保存个数据，新建一个Client.java类来存入一个数据。代码如下：
[java] view plain copy package com.bjpowernode.hibernate; import java.util.Date; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; public class Client { public static void main(String[] args) { //读取hibernate.cfg.xml文件 Configuration cfg = new Configuration().configure(); //建立SessionFactory SessionFactory factory = cfg.buildSessionFactory(); //取得session Session session = null; try { session = factory.openSession(); //开启事务 session.beginTransaction(); User user = new User(); user.setName("张三"); user.setPassword("123"); user.setCreateTime(new Date()); user.setExpireTime(new Date()); //保存User对象 session.save(user); //提交事务 session.getTransaction().commit(); }catch(Exception e) { e.printStackTrace(); //回滚事务 session.getTransaction().rollback(); }finally { if (session != null) { if (session.isOpen()) { //关闭session session.close(); } } } } }
一个简单的Hibernate例子就出来了在Hibernate初学时利用这个例子可以让我们更好的入门。
