整合MyBatis

首先创建一个sprinboot项目，并引入web,jbdc,mysql驱动依赖。

1、添加springboot整合myBatis的依赖

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.1.3</version>
</dependency>

2、配置数据库连接信息

spring:
  datasource:
    username: root
    password: 2824199842
    url: jdbc:mysql://localhost:3306/mybatis?serverTimezone=Asia/Shanghai
    driver-class-name: com.mysql.cj.jdbc.Driver

3、测试是否能连接成功

@SpringBootTest
class Springboot05MybatisApplicationTests {
    @Autowired
    DataSource dataSource;
    @Test
    void contextLoads() throws SQLException {
        Connection connection = dataSource.getConnection();
        System.out.println(connection);
    }
}

4、创建实体类，导入lombok

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.4</version>
</dependency>

User.java

package com.zyz.bean;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private Integer id;
    private String name;
    private String pwd;
}

5、创建mapper目录，以及对应的mapper接口

UserMapper.java

@Mapper// 表示这是一个mybatis的mapper类
@Repository
public interface UserMapper {

     List<User> listAllUser();

     User queryUserById(int id);

     int addUser(User user);

     int deleteUser(int id);

     int updateUser(User user);
}

6、创建对应的sql映射文件UserMapper.xml

在项目配置文件中添加mybatis配置

# mybatis配置
mybatis:
    type-aliases-package: com.zyz.bean # 设置别名 默认为类名
    mapper-locations: classpath:mybatis/mapper/*.xml # mapper文件位置
    configuration:
    	# 输出sql
    	log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
    	# 开启驼峰命名规则
    	map-underscore-to-camel-case: true

UserMapper.xml

<?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.zyz.mapper.UserMapper">
    <select id="listAllUser" resultType="User">
        select * from user
    </select>

    <select id="queryUserById" resultType="User">
        select * from user where id=#{id}
    </select>
    
    <insert id="addUser" parameterType="User">
        insert into user(name,pwd)values(#{name},#{password})
    </insert>
    
    <delete id="deleteUser" parameterType="int">
        delete from user where id=#{id}
    </delete>

    <update id="updateUser" parameterType="User">
        update user set name=#{name},pwd=#{pwd} where id=#{id}
    </update>
</mapper>

6、创建controller目录，添加UserController类

UserController.java

@RestController
public class UserController {
    @Autowired
    private UserMapper userMapper;

    @GetMapping("/listAllUser")
    public List<User> list(){
        return userMapper.listAllUser();
    }

    @GetMapping("/queryUserById/{id}")
    public User query(@PathVariable("id") int id){
        return userMapper.queryUserById(id);
    }

    @GetMapping("/addUser")
    public String add(){
        userMapper.addUser(new User(null,"马老师","123456"));
        return "add success";
    }
    @GetMapping("/deleteUser/{id}")
    public String delete(@PathVariable("id") int id){
        userMapper.deleteUser(id);
        return "delete success";
    }
    @GetMapping("/updateUser")
    public String update(){
        userMapper. updateUser(new User(1,"qwer","123456"));
        return "update success";
    }
}

到此为止，MyBatis整合完毕。