第一步：pom.xml

第二步：application.properties配置資料來源

#資料來源
spring.datasource.url=jdbc:mysql://localhost:3306/mybatis-demo?useUnicode=true&characterEncoding=utf-8
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.password=admine
spring.datasource.username=root

第三步：建立各層包

此處忽略不計

第四步：application.properties配置mybatis掃描對映

#mapper對映
mybatis.mapper-locations=classpath:mapper/*.xml
#mybatis.type-aliases-package=com.example.mybatis.demo.entity

#sql日誌
logging.level.com.example.mybatis.demo.mapper=debug

第五步：啟動類上新增持久層介面路徑

擴充套件步驟：mapper.xml格式

<?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.mybatis.demo.mapper.UserMapper">
    <resultMap id="ResultBeanMap" type="com.example.mybatis.demo.entity.User">
        <result property="id" column="id" jdbcType="DECIMAL"></result>
        <result property="name" column="name" jdbcType="VARCHAR"></result>
        <result property="age" column="age" jdbcType="DECIMAL"></result>
    </resultMap>

    <select id="findAll" resultMap="ResultBeanMap">
        SELECT 
 
* FROM user;
    </select>
</mapper>