SpringBoot之整合Mybatis

1、首先搭建起Spring Boot Web项目

链接地址https://mp.youkuaiyun.com/postedit/101756693

2、引入jar包

<!--    mybatis开始   -->

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>1.3.2</version>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.38</version>
    <!--<scope>runtime</scope>-->
</dependency>

<!--    mybatis结束   -->

3、引入配置文件

spring:
  datasource:
    username: root
    password: root
    url: jdbc:mysql://localhost:3306/springboot?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver

mybatis:
  mapper-locations: classpath:mapping/*Mapper.xml
  type-aliases-package: com.example.demo

4、创建数据库和表

 create table springboot.user
(
    id bigint not null AUTO_INCREMENT comment '主键' primary key,
    age int null comment '年龄',
    password varchar(32) null comment '密码',
    sex int null comment '性别',
    username varchar(32) null comment '用户名'
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

 

5、扫描mapper层

 

6、mapper层

@Repository
public interface UserMapper {

    User Sel(int id);

}

7、service层

@Service
public class UserService {

    @Autowired
    private UserMapper userMapper;

    public User Sel(int id) {
        return userMapper.Sel(id);
    }
}

8、entity层

public class User {
    private Integer id;
    private String userName;
    private String passWord;
    private String realName;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassWord() {
        return passWord;
    }

    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }

    public String getRealName() {
        return realName;
    }

    public void setRealName(String realName) {
        this.realName = realName;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", userName='" + userName + '\'' +
                ", passWord='" + passWord + '\'' +
                ", realName='" + realName + '\'' +
                '}';
    }
}

 

9、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.example.demo.mapper.UserMapper">

    <resultMap id="BaseResultMap" type="com.example.demo.entity.User">
        <result column="id" jdbcType="INTEGER" property="id" />
        <result column="userName" jdbcType="VARCHAR" property="userName" />
        <result column="passWord" jdbcType="VARCHAR" property="passWord" />
        <result column="realName" jdbcType="VARCHAR" property="realName" />
    </resultMap>

    <select id="Sel" resultType="com.example.demo.entity.User">
        select * from user where id = #{id}
    </select>

</mapper>

 

10启动项目则可以访问该接口

//访问/hello或者/hi任何一个地址，都会返回一样的结果
@RequestMapping(value = {"/getUser"}, method = RequestMethod.GET)
public String getUser(@RequestParam Integer id) {
    if (id==null)
        return null;
    return userService.Sel(id).toString();
}