问题描述：
SpringBoot项目启动报错，报错内容：‘com.xxx.mapper.XxxxMapper’ that could not be found

*************************** APPLICATION FAILED TO START

---

Description:

Field userMapper in com.demo.controller.MemberController required a
bean of type ‘com.demo.mapper.UserMapper’ that could not be found.

Action:

Consider defining a bean of type ‘com.demo.mapper.UserMapper’ in your
configuration.

Process finished with exit code 1

问题原因：未扫描到mapper

解决方式：启动类中添加@MapperScan("com.demo.mapper")