<!--springboot mybatis持久层框架-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.0</version>
        </dependency>
        <!--springboot mybatis通用工具mapper-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.1.5</version>
        </dependency>
        <!--springboot mybatis分页PageHelper助手类-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.12</version>
        </dependency>

xml头部和案例

<?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="org.mybatis.example.BlogMapper">
  <select id="selectBlog" resultType="Blog">
    select * from Blog where id = #{id}
  </select>
</mapper>

application.properties追加

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

resources>mybatis>mapper>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.xuwen.mapper.UserMapper">
    <select id="queryUserList" resultType="com.xuwen.pojo.User">
        select * from koa2weibo.user
    </select>

    <select id="queryUserById" resultType="com.xuwen.pojo.User">
        select * from koa2weibo.user where id=#{id}
    </select>

    <insert id="addUser" parameterType="com.xuwen.pojo.User">
        insert into koa2weibo.user (id,name,pwd) values(#{id},#{name},#{pwd})
    </insert>

    <update id="UpdateUser" parameterType="com.xuwen.pojo.User">
        update koa2weibo.user set name=#{name}, pwd=#{pwd} where id=#{id}
    </update>

    <delete id="deleteUser" parameterType="int">
        delete from koa2weibo.user where id=#{id}
    </delete>
</mapper>

controller层

package com.xuwen.controller;

import com.xuwen.mapper.UserMapper;
import com.xuwen.pojo.User;
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;

/**
 * author:xuwen
 * Created on 2021/8/3
 */
@RestController
public class UserController {

    @Autowired
    private UserMapper userMapper;

    //查询全部用户
    @GetMapping("/queryUserList")
    private List<User> queryUserList(){
        List<User> userList = userMapper.queryUserList();
        for (User user : userList) {
            System.out.println(user);
        }
        return userList;
    }

//增加
    @GetMapping("/addUser")
    public String addUser(){
        userMapper.addUser(new User(8,"毛毛","jfejife55"));
        return "ok";
    }


    //修改
    @GetMapping("/updateUser")
    public String updateUser(){
        userMapper.UpdateUser(new User(8,"毛毛","jfejife55"));
        return "ok";
    }


    //删除
    @GetMapping("/deleteUser")
    public String deleteUser(){
        userMapper.deleteUser(5);
        return "ok";
    }



}

applicaiton.yml

spring:
  datasource:
    username: koa2weibo
    password: passMYblog123
    url: jdbc:mysql://rm-uf6t9m0yx22dxrya5no.mysql.rds.aliyuncs.com:3306/koa2weibo?serverTimezone=Asia/Shanghai&useSSL=true&useUnicode=true&characterEncoding=UTF8
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource

    #SpringBoot默认是不注入这些的，需要自己绑定
    #druid数据源专有配置
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true

    #配置监控统计拦截的filters，stat：监控统计、log4j：日志记录、wall：防御sql注入
    #如果允许报错，java.lang.ClassNotFoundException: org.apache.Log4j.Properity
    #则导入log4j 依赖就行
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionoProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500