Hibernate的基本开发流程

一、Hibernate开发的基本流程

                                   


二、Hibernate开发的环境搭建

1、引入Hibernate核心包以及Hibernate依赖包即可。可以在Hibernate目录下的\lib\required目录下找到所需jar包。



2、加入数据库驱动。这里主要是采用Mysql数据库来操作，所以在这里引入MysqL的JDBC驱动。

3、提供核心配置文件hibernate.cfg.xml文件（在src文件夹下即可）。



三、数据库方面的操作

在mysql中新建一个数据库Hibernate5，然后建立如下的一个表来进行测试。

create table T_register

(

    id    int primary key,

    userName varchar(30),

    userPwd varchar(30),

    sex varchar(10),

    age int

)



四、编写POJO类

根据数据表的字段情况，创建如下持久化类，实际上是一个javaBean类

package com.chen;

public class TRegister{

//定义基本属性，与数据库中的字段对应。注意都是引用类型

private Integer id;
private String userName;
private String userPwd;
private String sex;
private Integer age;

// Constructors

/** default constructor */
public TRegister() {
}

/** minimal constructor */
public TRegister(Integer id) {
this.id = id;
}

/** full constructor */
public TRegister(Integer id, String userName, String userPwd, String sex, Integer age) {
this.id = id;
this.userName = userName;
this.userPwd = userPwd;
this.sex = sex;
this.age = age;
}

// 定义get set方法

public Integer getId() {
return this.id;
}

public void setId(Integer id) {
this.id = id;
}

public String getUserName() {
return this.userName;
}

public void setUserName(String userName) {
this.userName = userName;
}

public String getUserPwd() {
return this.userPwd;
}

public void setUserPwd(String userPwd) {
this.userPwd = userPwd;
}

public String getSex() {
return this.sex;
}

public void setSex(String sex) {
this.sex = sex;
}

public Integer getAge() {
return this.age;
}

public void setAge(Integer age) {
this.age = age;
}
}

五、配置相关的xml文件

1、配置hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>

<!-- 配置连接数据库的基本信息 -->
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://192.168.1.148:3306/hibernate5</property>

<!-- 配置 hibernate 的基本信息 -->
<!-- hibernate 所使用的数据库方言 -->
<property name="dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>

<!-- 执行操作时是否在控制台打印 SQL -->
<property name="show_sql">true</property>
<!-- 是否对 SQL 进行格式化 -->
<property name="format_sql">true</property>
<!-- 指定关联的 .hbm.xml 文件 -->
<mapping resource="com/chen/TRegister.hbm.xml"/>

</session-factory>

</hibernate-configuration>

注意：Hibernate4连接MySQL5.X数据库无法自动创建表，解决方法把数据库方言设为

<property name="dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>

2、配置映射文件TRegister.hbm.xml 

在持久化类所在的包中建立TRegister.hbm.xml ,可以通过eclipse Hibernate插件来完成

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 2017-3-7 22:14:28 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
<class name="com.chen.TRegister" table="TREGISTER">
<id name="id" type="java.lang.Integer">
<column name="ID" />
<!-- 我在MYSQL中并没有设置该字段递增，但在Hibernate中依然可以设置为递增 -->
<generator class="increment" />
</id>
<property name="userName" type="java.lang.String">
<column name="USERNAME" />
</property>
<property name="userPwd" type="java.lang.String">
<column name="USERPWD" />
</property>
<property name="sex" type="java.lang.String">
<column name="SEX" />
</property>
<property name="age" type="java.lang.Integer">
<column name="AGE" />
</property>
</class>
</hibernate-mapping>

六、编写事务处理类HibernateUtil.java

package hibernate;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;

public class HibernateUtil {

private static final SessionFactory sessionFactory;

static
{
try
{
Configuration config = new Configuration().configure();
ServiceRegistry serviceRegistry=
new ServiceRegistryBuilder().applySettings(config.getProperties())
.buildServiceRegistry();
sessionFactory = config.buildSessionFactory(serviceRegistry);
}
catch(Throwable e)
{
throw new ExceptionInInitializerError(e);
}
}

public static final ThreadLocal session = new ThreadLocal();

public static Session currentSession() throws HibernateException
{
Session s = (Session)session.get();
//Open a new Session,if this Thread has none yet
if(s == null || !s.isOpen())
{
s = sessionFactory.openSession();
session.set(s);
}
return s;
}

public static void closeSession() throws HibernateException
{
Session s = (Session)session.get();
session.set(null);
if(s != null)
s.close();
}

}

七、编写Servlet控制类RegisterServlet

package servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.chen.TRegister;

import hibernate.HibernateUtil;

/**
* Servlet implementation class RegisterServlet
*/
@WebServlet("/RegisterServlet")
public class RegisterServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final String CONTENT_TYPE = "text/html;charset=GBK";
/**
* @see HttpServlet#HttpServlet()
*/
public RegisterServlet() {
super();
// TODO Auto-generated constructor stub
}

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType(CONTENT_TYPE);
request.setCharacterEncoding("GBK");

PrintWriter out = response.getWriter();

String userName = request.getParameter("userName");
String userPwd = request.getParameter("userPwd");
String sex = request.getParameter("sex");
int age = Integer.parseInt(request.getParameter("age"));

TRegister rg = new TRegister();
rg.setAge(age);
rg.setSex(sex);
rg.setUserName(userName);
rg.setUserPwd(userPwd);

Session session = HibernateUtil.currentSession();//生成Session实例
Transaction tx = session.beginTransaction();

try
{
session.save(rg);    //保存持久类对象
tx.commit();        //提交到数据库
session.close();
response.sendRedirect("registerOK.jsp");
}
catch(HibernateException e)
{
e.printStackTrace();
tx.rollback();
}

}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}

}

八、编写jsp页面进行测试

1、register.jsp

<%@ page language="java" contentType="text/html; charset=GBK"
pageEncoding="GBK"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GBK">
<title>Insert title here</title>
</head>
<body>

<form action="RegisterServlet" method="POST">
用户名：<input type="text" name="userName" /><BR>
密  码：<input type="text" name="userPwd" /><BR>
性  别：<input type="text" name="sex" /><BR>
年  龄：<input type="text" name="age" /><BR>
<input type="submit" value="save" />
</form>
</body>
</html>

2、registerOK.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
数据已保存到数据库，请查看.......
</body>
</html>

九、运行验证

运行register.jsp页面，填写信息，完成后点击save完成保存。查看数据库可以看到数据已保存。