Springboot整合Mybaits

Posted 2021-02-20 学习笔记

1.导入mybatis-spring-boot-starter依赖

<!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.1.2</version>
</dependency>

2.创建实体类User

package com.example.pojo;

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

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

3.创建dao层UserMapper

package com.example.dao;

import com.example.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;

import java.util.List;

@Mapper
@Repository
public interface UserMapper {
    //查询全部用户
    List<User> getUserList();

    //根据id查询用户
    User selectUserById(int id);

    //添加一个用户
    int addUser(User user);

    //修改一个用户
    int updateUser(User user);

    //根据id删除用户
    int deleteUserById(int id);
}

4.创建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">
<!--namespace=绑定一个对应的Dao/Mapper接口-->
<mapper namespace="com.example.dao.UserMapper">

    <!--select查询语句-->
    <select id="getUserList" resultType="user">
       select * from user
   </select>

    <select id="selectUserById" resultType="user" parameterType="int">
        select * from user where id=#{id}
    </select>

    <insert id="addUser" parameterType="user">
        insert into user (id,name,pwd) values (#{id},#{name},#{pwd})
    </insert>

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

    <delete id="deleteUserById" parameterType="int">
        delete from user where id = #{id}
    </delete>

</mapper>

5.编辑配置文件

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://192.168.137.100:3306/mybatis?useSSL=false&useUnicode=true&characterEncoding=UTF-8&allowPublicKeyRetrieval=true
spring.datasource.username=root
spring.datasource.password=root

#mybatis配置
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.example.pojo

6.创建控制器

package com.example.controller;

import com.example.dao.UserMapper;
import com.example.pojo.User;
import lombok.val;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class HomeController {

    @Autowired
    private UserMapper userMapper;

    @GetMapping("/test")
    public List<User> test(){
        val userList = userMapper.getUserList();
        return userList;
    }
}