Spring Boot Mybatis，使用mapper接口和xml配置sql

最近学习Spring Boot搭建web应用，连接数据库，使用Mapper接口和xml配置，记录自己的学习过程：

1.首先在配置文件application.yml或者application.properties（yml和properties区别自行学习下）中，写上相关的信息

mybatis:
  type-aliases-package: com.persimmon.springboot.Entity
  mapper-locations: classpath*:mapper/*Mapper.xml

2.在启动类Application.java中写上配置信息

@SpringBootApplication
@MapperScan("com.persimmon.springboot.Mapper")
public class SpringbootApplication {
}

3.写mapper.xml文件

<?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.persimmon.springboot.Mapper.UserMapper">

    <resultMap id="RequestMap" type="com.persimmon.springboot.Entity.UserEntity">
        <result column="id" property="id" jdbcType="BIGINT"></result>
        <result column="openid" property="openid" jdbcType="VARCHAR"/>
        <result column="seesion_key" property="seesion_key" jdbcType="VARCHAR"/>
        <result column="create_time" property="createTime" jdbcType="TIMESTAMP"/>
        <result column="update_time" property="updateTime" jdbcType="TIMESTAMP"/>
        <result column="is_delete" property="isDelete" jdbcType="INTEGER"/>
        <result column="appid" property="appid" jdbcType="VARCHAR"/>
    </resultMap>
    
    <select id="findAll" resultMap="RequestMap">
        select * from user_tb
    </select>

</mapper>

4.*mapper加注解

配置完成。