IntelliJ IDEA spring mvc +mybatis 环境搭建服务器(下)

上篇是使用xml配置来完成mysql数据库的操作，本文将使用注解形式，当然由于本文是较基础的入门级，存在许多地方欠考虑的地方，请大家多包涵。由于代码较简单就省略注释和讲解了。

来自我的简书： http://www.jianshu.com/p/32f15e199572

直接使用类来生成Mapper：

package com.nothing.Mapper;import com.nothing.Model.User;import org.apache.ibatis.annotations.Insert;import org.apache.ibatis.annotations.Select;import java.util.List;public interface UserMapper {    @Select("select * from user_nothing where id = #{id}")    User findUserById(int id);    @Insert("insert into user_nothing(username,password) values(#{username},#{password})")    void addUser(User user);    @Select("select * from user_nothing")    List<User> getAllUsers();}

三个方法分别是向mysql数据库中user_nothing表单条查询、添加、列表查询。
基本上与userMapper.xml的句子一直（这里添加了一个查询所有用户的语句），这里再次黏贴一下代码，便于比较：

<mapper namespace="userMapper">    <!--根据ID获取对应的值  -->    <select id="findUserById" parameterType="int" resultType="com.nothing.Model.User">        select * from user_nothing where id = #{id}    </select>    <insert id="addUser" parameterType="com.nothing.Model.User">            insert into user_nothing(username,password) values(#{username},#{password})    </insert></mapper>

本文因此就不需要userMapper.xml了。

需要修改的config没什么改动，仅仅需要注意添加的mapper即可。

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE configuration        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-config.dtd"><configuration>    <!-- development:开发模式     work:工作模式 -->    <environments default="development">        <environment id="development">            <transactionManager type="JDBC" />            <dataSource type="POOLED">                <property name="driver" value="com.mysql.jdbc.Driver" />                <property name="url" value="jdbc:mysql://localhost:3306/mysql" />                <property name="username" value="root" />                <property name="password" value="123456" />            </dataSource>        </environment>    </environments>    <mappers>        <mapper class="com.nothing.Mapper.UserMapper"/>    </mappers></configuration>

为便于读者使用将之前的Dao和Service类都再贴出来：

public interface IUserDao {    User findUserById(int id);    void addUser(User user);    List<User> getAllUsers();}

注意注释部分是使用xml时配置。

public class UserDaoImpl implements IUserDao{    private  SqlSessionFactory sessionFactory;    private  SqlSession session;    private UserMapper mapper;    public UserDaoImpl() {        String resource = "conf.xml";        try {            Reader reader = Resources.getResourceAsReader(resource);            sessionFactory = new SqlSessionFactoryBuilder().build(reader);            session = sessionFactory.openSession();            mapper = session.getMapper(UserMapper.class);        } catch (IOException e) {            e.printStackTrace();        }    }    public User findUserById(int id) {//        String statement = "userMapper.findUserById";//        User user = (User)session.selectOne(statement, id);//        return user;        return mapper.findUserById(id);    }    public void addUser(User user) {//        String statement = "userMapper.addUser";//        session.insert(statement, user);        mapper.addUser(user);        session.commit();    }    public List<User> getAllUsers() {        return mapper.getAllUsers();    }}

public interface IUserService {    User findUserById(int id);    void addUser(User user);    List<User> getAllUsers();}

public class UserServiceImpl implements IUserService{    private IUserDao userDao;    public UserServiceImpl() {        userDao = new UserDaoImpl();    }    public User findUserById(int id) {        return userDao.findUserById(id);    }    public void addUser(User user){        userDao.addUser(user);    }    public List<User> getAllUsers() {        return userDao.getAllUsers();    }}

这里唠叨一下，最近学习mvp模式时，突然觉得移动的mvp框架不就是这个Service作用么。

最后贴一下Controller

@Controllerpublic class MainController {    private IUserService service = new UserServiceImpl();    @RequestMapping(value = "/hello", method = RequestMethod.GET)    public String index( User user) {        return "index";    }    @RequestMapping(value="nice",method = RequestMethod.GET)    @ResponseBody    public  List<User> nice(Model model){       return service.getAllUsers();    }    @RequestMapping(value ="/toJson",method=RequestMethod.POST)    @ResponseBody    public User toJson(User user){        service.addUser(user);        return service.findUserById(2);    }}

运行返回所有用户的页面截图的结果图。是不是很简单？

Paste_Image.png