准备

1.官网上下载MyBatis安装包

下载地址https://github.com/mybatis/mybatis-3/releases

2.准备好数据库

 

 3.创建maven工程

 

 删除src

4.导入依赖

在pom.xml中输入以下代码

左上角的刷新自动配置依赖

防止导出出现问题还需要配置

5.创建子模块

右键添加一个Module新建maven工程，配置如图

6.配置mybatis-config.xml 文件

在resourse中新增一个xml文件配置核心文件并按照自己的用户名和密码修改

 

7.创建工具实体和接口类

完整目录如下

里面的MybatisUtils代码如下

package com.robot.utils;
 
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
 
import java.io.IOException;
import java.io.InputStream;
 
public class MybatisUtils {
 
    private static SqlSessionFactory sqlSessionFactory;
    static {
        try {
            String source = "mybatis-config.xml";
            InputStream inputStream = null;
            inputStream = Resources.getResourceAsStream(source);
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
 
    // 获取SqlSession
    public static SqlSession getSqlSession() {
        return sqlSessionFactory.openSession();
    }
 
}

 User代码如下

package com.robot.pojo;
 
public class User {
    private int id;
    private String name;
    private String pwd;
 
    public User() {
    }
 
    public User(int id, String name, String pwd) {
        this.id = id;
        this.name = name;
        this.pwd = pwd;
    }
 
    public int getId() {
        return id;
    }
 
    public void setId(int id) {
        this.id = id;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public String getPwd() {
        return pwd;
    }
 
    public void setPwd(String pwd) {
        this.pwd = pwd;
    }
 
    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", pwd='" + pwd + '\'' +
                '}';
    }
}

 创建接口的代码如下（实现其他功能就是修改接口方法并配置相应的xml文件并测试）

package com.robot.dao;
 
import com.robot.pojo.User;
 
import java.util.List;
 
public interface UserMapper {
    // 查询全部用户
    List<User> getUserList();
 
    // 根据ID查询用户
    User getUserById(int id);
 
    // 插入用户
    int addUser(User user);
 
    // 修改用户
    int updateUser(User user);
 
    // 删除用户
    int deleteUser(int id);
}

 8.配置接口对应的xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 
<mapper namespace="com.robot.dao.UserMapper">
<!--    select all-->
    <select id="getUserList" resultType="com.robot.pojo.User">
        select * from mybatis.user
    </select>
 
<!--    select one-->
    <select id="getUserById" parameterType="int" resultType="com.robot.pojo.User">
        select * from mybatis.user WHERE id = #{id}
    </select>
 
<!--    add user-->
    <insert id="addUser" parameterType="com.robot.pojo.User">
        insert into mybatis.user (id, name, pwd) values (#{id}, #{name}, #{pwd})
    </insert>
 
<!--    update user-->
    <update id="updateUser" parameterType="com.robot.pojo.User">
        update mybatis.user set name=#{name}, pwd=#{pwd} where id=#{id};
    </update>
 
<!--    delete user-->
    <delete id="deleteUser" parameterType="int">
        delete from mybatis.user where id = #{id}
    </delete>
</mapper>

之前的xml文件中记得重新配置，修改mappers标签令他连接到此xml文件

<mappers>
    <mapper resource="com/robot/dao/UserMapper.xml"/>
</mappers>

9.测试

test里面创建java类测试

package com.robot.dao;
 
import com.robot.pojo.User;
import com.robot.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
 
import java.util.List;
 
public class UserDaoTest {
 
    @Test
    public void getUserListTest() {
        // 1.获得SqlSession对象
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        // 2.执行SQL
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        List<User> userList = userMapper.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }
        sqlSession.close();
    }
 
    @Test
    public void getUserByIdTest() {
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = userMapper.getUserById(1);
        System.out.println(user);
        sqlSession.close();
    }
 
    @Test
    public void addUserTest() {
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        int res = userMapper.addUser(new User(4, "baby2", "123456"));
        System.out.println(res);
        // 提交事务
        sqlSession.commit();
        sqlSession.close();
    }
 
    @Test
    public void updateUserTest() {
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        int res  = userMapper.updateUser(new User(4, "mybaby", "125888"));
        System.out.println(res);
        sqlSession.commit();
        sqlSession.close();
    }
 
    @Test
    public void deleteUserTest() {
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        userMapper.deleteUser(4);
        sqlSession.commit();
        sqlSession.close();
    }
}