【hibernate进阶】hibernate搭建开发环境+实例讲解

本篇博客将带着大家以一个简单的实例来学习hibernate项目。

1、创建java项目

2、创建User Library，加入依赖包
* HIBERNATE_HOME/lib/*.jar
* HIBERNATE_HOME/hibernate3.jar

* 加入数据库驱动（mysql驱动）

具体的操作步骤参考我的上一篇博客：【hibernate进阶】如何在myeclipse中添加jar包

3、提供hibernate.cfg.xml文件，完成基本的配置

<strong><span style="font-size:18px;"><!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_first</property>        <property name="hibernate.connection.username">root</property>        <property name="hibernate.connection.password">123</property>        <!-- mysql language adatper，if you want to change database ,you juse need to change there  -->        <!-- <property name="hibernate.connection.dialect">org.hibernate.dialect.MySQLDialect</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></span></strong>

4、建立实体类User.java

<strong><span style="font-size:18px;"><strong><span style="font-size:18px;">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;}}</span></strong></span></strong>

5、提供User.hbm.xml文件，完成实体类的映射

<strong><span style="font-size:18px;"><?xml version="1.0"?><!DOCTYPE hibernate-mapping SYSTEM "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></span></strong>

6、将User.hbm.xml文件加入到hibernate.cfg.xml文件中

这个在3步的时候已经加进去了

7、编写工具类ExoprtDB.java,将hbm生成ddl，也就是hbm2ddl

<strong><span style="font-size:18px;">package com.bjpowernode.hibernate;import org.hibernate.cfg.Configuration;import org.hibernate.tool.hbm2ddl.SchemaExport;/** * hbm  Generation ddl * @author CXC * */public class ExoprtDB {public static void main(String[] args){//Read by default hibernate.cfg.xml FileConfiguration cfg=new Configuration().configure();SchemaExport export=new SchemaExport(cfg);export.create(true, true);}}</span></strong>

在这一步的时候，就可以生成user表了，run as java application ，查看数据库，就可以生成user表了。

8、建立客户端类Client，添加用户数据到mysql

<strong><span style="font-size:18px;">package com.bjpowernode.hibernate;import java.text.SimpleDateFormat;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) {//read hibernate.cfg.xml fileConfiguration  cfg=new Configuration().configure();//sessionfactory thread safe//build sessionfactorySessionFactory factory=cfg.buildSessionFactory();//acquire session Session session=null;try{session=factory.openSession();//open Transactionsession.beginTransaction();User user=new User();user.setName("12");user.setPassword("123");/*  user.setCreateTime(new Date()); user.setExpireTime(new Date());*/Date date=new Date();                                         SimpleDateFormat temp=new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");               String date2=temp.format(date);               Date date3=temp.parse(date2);                            user.setCreateTime(date3); user.setExpireTime(date3);//save User objectsession.save(user);//commit Transactionsession.getTransaction().commit();}catch(Exception e){e.printStackTrace();//rollback  Transactionsession.getTransaction().rollback();}finally{if(session !=null){if(session.isOpen()){//close sessionsession.close();}}}}}</span></strong>

在console中，输入的insert into user(.....)信息表示将数据插入到数据库中了。

通过navicat，查看插入的数据

这样，hibernate的项目就完成了。

遇到的问题：

在插入的时候，遇到了日期插不进去的问题。以为是mysql引用的jar包问题，重新引用了没有解决，想到了在之前也遇到过类似的问题，把转了一下日期的格式就解决了。