（详细教程）Springboot整合Mybatis

新建项目过程省略

1.首先pom.xml引入Maven依赖

  <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>

2.application.yml配置mysql数据库 并且整合Mybatis框架

项目结构如下图(只需要关注箭头所指处)：

spring:#配置mysql数据库
  datasource:
    username: root
    password: *****
    #?serverTimezone=UTC解决时区的报错
    url: jdbc:mysql://localhost/Mybatis? 
         serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
    driver-class-name: com.mysql.cj.jdbc.Driver

#整合mybatis
mybatis:
  type-aliases-package: com.springboot.systemmanage.systemmanage.pojo
  mapper-locations: classpath:mybatis/mapper/*.xml

3.编写配置文件编写代码

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.springboot.systemmanage.systemmanage.mapper.UserMapper">
    <select id="queryUserList" resultType="User">/*即使是List resultType返回类型 也为User类型*/
        select * from user
   </select>

    <select id="queryUserById" resultType="User">/*resultType返回类型 也为User类型*/
        select * from user where id=#{id}
    </select>

    <insert id="addUser" parameterType="User">/*parameterType 传递参数为User类型*/
        insert  into user(id,name,pwd) values (#{id},#{name},#{pwd})
    </insert>

    <update id="updateUser" parameterType="User">/*parameterType 传递参数为User类型*/
        update user set name=#{name},pwd=#{pwd} where id=#{id}
    </update>

    <delete id="deleteUser" parameterType="int">/*parameterType 传递参数为Int类型*/
        delete form user  where  id=#{id}
    </delete>


</mapper>

User对象

/**
 * @Author MRyan
 * @Date 2020/2/9 18:21
 * @Version 1.0
 */
@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private int id;
    private String name;
    private String pwd;
}

UserMapper

/**
 * @Author MRyan
 * @Date 2020/2/9 18:16
 * @Version 1.0
 */

//Repository将DAO类声明为Bean 其次在xml配置文件中启动spring自动扫描功能
@Mapper
@Repository
public interface UserMapper {

    List<User> queryUserList();

    User queryUserById(int id);

    int addUser(User user);

    int updateUser(User user);

    int deleteUser(int id);

}

最后使我们的实现代码部分：
UserController.java

/**
 * @Author MRyan
 * @Date 2020/2/9 18:50
 * @Version 1.0
 */
@RestController
public class UserController {

    @Autowired
    private UserMapper userMapper;

    //查询所有用户
    @GetMapping("/queryUserList")
    public List<User> queryUserList(){
        List<User> users = userMapper.queryUserList();
        return users;
    }

    //根据id查询一个用户
    @GetMapping("/queryUserById/{id}")
    public String queryUserById(@PathVariable(value = "id") int id){
        User user = userMapper.queryUserById(id);
        return "success insert"+user;
    }


    //添加一个用户
    @GetMapping("/addUser")
    public String addUser(){
        userMapper.addUser(new User(5,"MRYAN","123456"));
        return "success add";
    }

    //修改用户
    @GetMapping("/updateUser")
    public String updateUser(){
        userMapper.updateUser(new User(5,"MRYAN","123456"));
        return "success update";
    }

    //根据id删除一个用户
    @GetMapping("deleteUser/{id}")
    public String deleteUser(@PathVariable(value = "id") int id){
        userMapper.deleteUser(id);
        return "success delete";
    }

}

以上就整合了Mybatis简单实现了增删改查功能