## 一、总体说明
本例运行演示了用Jersey构建RESTful服务中，如何同过Hibernate将数据持久化进MySQL的过程
## 二、环境
1.上文的项目RestDemo
2.MySQL5.6下载[http://dev.mysql.com/get/Downloads/MySQL-5.6/mysql-5.6.16-win32.zip](http://sourceforge.net/projects/hibernate/files/hibernate4/4.3.4.Final/hibernate-release-4.3.4.Final.zip)
3.Hibernate4.3.4下载[http://sourceforge.net/projects/hibernate/files/hibernate4/4.3.4.Final/hibernate-release-4.3.4.Final.zip](http://sourceforge.net/projects/hibernate/files/hibernate4/4.3.4.Final/hibernate-release-4.3.4.Final.zip)
4.Java程序连接MySQL的驱动mysql-connector-java-5.1.29-bin.jar下载
[http://dev.mysql.com/get/Downloads/Connector-J/mysql-connector-java-5.1.29.zip](http://dev.mysql.com/get/Downloads/Connector-J/mysql-connector-java-5.1.29.zip)
## 三、数据库准备
1.搭建MySQL数据库
2.创建数据库RestDemo ,及数据表t_user,结构如下
DROP TABLE IF EXISTS `t_user`;
CREATE TABLE `t_user` (
`userId` varchar(50) NOT NULL,
`userName` varchar(50) NOT NULL,
`age` varchar(50) NOT NULL,
PRIMARY KEY (`userId`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
ps: userId 非自增长类型，需要在业务添加
## 四、引入Hibernate
1.解压Hibernate的包，在lib\required文件夹下所有jar引入进项目
2.解压mysql-connector-java-5.1.29.zip，将mysql-connector-java-5.1.29-bin.jar引入进项目
3.在项目的根目录创建hibernate的配置文件hibernate.cfg.xml，内容如下：
~~~
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://127.0.0.1:3306/RestDemo</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">update</property>
<mapping resource="com/waylau/rest/bean/User.hbm.xml"/>
</session-factory>
</hibernate-configuration>
~~~
4.在项目User.java 的同个目录下，创建该类的映射文件User.hbm.xml
~~~
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="com.waylau.rest.bean">
<class name="User" table="T_USER">
<id name="userId" column="USERID" type="string" >
<generator class="assigned"/>
</id>
<property name="userName" type="string" />
<property name="age" type="string" />
</class>
</hibernate-mapping>
~~~
5.创建包com.waylau.rest.util，在该包下创建HibernateUtil.java
~~~
package com.waylau.rest.util;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
/**
* Hibernate 初始化配置工具类
* @author waylau.com
* 2014-3-23
*/
public class HibernateUtil {
private static Configuration configuration;
private static SessionFactory sessionFactory;
private static StandardServiceRegistry standardServiceRegistry;
static {
try {
//第一步:读取Hibernate的配置文件 hibernamte.cfg.xml文件
configuration = new Configuration().configure("hibernate.cfg.xml");
//第二步:创建服务注册构建器对象，通过配置对象中加载所有的配置信息
StandardServiceRegistryBuilder sb = new StandardServiceRegistryBuilder();
sb.applySettings(configuration.getProperties());
//创建注册服务
standardServiceRegistry = sb.build();
//第三步:创建会话工厂
sessionFactory = configuration.buildSessionFactory(standardServiceRegistry);
} catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
~~~
6.在项目中建com.waylau.rest.dao包，在该包下建立User操作的接口UserDao.java
~~~
package com.waylau.rest.dao;
import java.util.List;
import com.waylau.rest.bean.User;
/**
* User Dao 接口
* @author waylau.com
* 2014-3-18
*/
public interface UserDao {
public User getUserById(String id);
public boolean deleteUserById(String id);
public boolean createUser(User user);
public boolean updateUser(User user);
public List<User> getAllUsers();
}
~~~
7.在项目中建com.waylau.rest.dao.impl包，在该包下建立User操作接口的实现UserDaoImpl.java
~~~
package com.waylau.rest.dao.impl;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import com.waylau.rest.bean.User;
import com.waylau.rest.dao.UserDao;
import com.waylau.rest.util.HibernateUtil;
/**
* 用户DAO实现
* @author waylau.com
* 2014-3-23
*/
public class UserDaoImpl implements UserDao {
@Override
public User getUserById(String id) {
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session s = null;
Transaction t = null;
User user = null;
try{
s = sessionFactory.openSession();
t = s.beginTransaction();
String hql = "from User where userId="+id;
Query query = s.createQuery(hql);
user = (User) query.uniqueResult();
t.commit();
}catch(Exception err){
t.rollback();
err.printStackTrace();
}finally{
s.close();
}
return user;
}
@Override
public boolean deleteUserById(String id) {
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session s = null;
Transaction t = null;
boolean flag = false;
try{
s = sessionFactory.openSession();
t = s.beginTransaction();
User user = new User();
user.setUserId(id);
s.delete(user);
t.commit();
flag = true;
}catch(Exception err){
t.rollback();
err.printStackTrace();
}finally{
s.close();
}
return flag;
}
@Override
public boolean createUser(User user) {
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session s = null;
Transaction t = null;
boolean flag = false;
try{
s = sessionFactory.openSession();
t = s.beginTransaction();
s.save(user);
t.commit();
flag = true;
}catch(Exception err){
t.rollback();
err.printStackTrace();
}finally{
s.close();
}
return flag;
}
@Override
public boolean updateUser(User user) {
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session s = null;
Transaction t = null;
boolean flag = false;
try{
s = sessionFactory.openSession();
t = s.beginTransaction();
s.update(user);
t.commit();
flag = true;
}catch(Exception err){
t.rollback();
err.printStackTrace();
}finally{
s.close();
}
return flag;
}
@Override
public List<User> getAllUsers() {
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session s = null;
Transaction t = null;
List<User> uesrs = null;
try{
s = sessionFactory.openSession();
t = s.beginTransaction();
String hql = "select * from t_user";
Query query = s.createSQLQuery(hql).addEntity(User.class);
query.setCacheable(true); // 设置缓存
uesrs = query.list();
t.commit();
}catch(Exception err){
t.rollback();
err.printStackTrace();
}finally{
s.close();
}
return uesrs;
}
}
~~~
8.修改项目中 com.waylau.rest.resources包下的UserResource.java，使之前在内存中模拟CURD转为在数据库中实现
~~~
package com.waylau.rest.resources;
import java.util.ArrayList;
import java.util.List;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.Consumes;
import javax.ws.rs.PathParam;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.DELETE;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.PUT;
import com.waylau.rest.bean.User;
import com.waylau.rest.dao.impl.UserDaoImpl;
/**
* 用户资源
* @author waylau.com
* 2014-3-19
*/
@Path("/users")
public class UserResource {
private UserDaoImpl userDaoImpl = new UserDaoImpl();
/**
* 增加
* @param user
*/
@POST
@Consumes({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
public void createUser(User user)
{
userDaoImpl.createUser(user);
}
/**
* 删除
* @param id
*/
@DELETE
@Path("{id}")
public void deleteUser(@PathParam("id")String id){
userDaoImpl.deleteUserById(id);
}
/**
* 修改
* @param user
*/
@PUT
@Consumes(MediaType.APPLICATION_XML)
public void updateUser(User user){
userDaoImpl.updateUser(user);
}
/**
* 根据id查询
* @param id
* @return
*/
@GET
@Path("{id}")
@Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
public User getUserById(@PathParam("id") String id){
User u = userDaoImpl.getUserById(id);
return u;
}
/**
* 查询所有
* @return
*/
@GET
@Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
public List<User> getAllUsers(){
List<User> users = new ArrayList<User>();
users = userDaoImpl.getAllUsers();
return users;
}
}
~~~
## 五、运行
1.将服务端运行后
2.运行UserClient客户端，可以看到数据库已经实现增删改查
完整项目架构如下：
================完整项目代码已经上传======
https://github.com/waylau/Restdemo
