@org.springframework.beans.factory.annotation.Autowired(required=true)-------不了解，粗心惹得祸，不懂惹得祸

   大家好，我是遇到爱你三千遍斯塔克，今天敲代码很高兴又遇到了一个bug，本着有bug必须消灭的原则，开始细心的搞吧！！，

***************************

APPLICATION FAILED TO START

***************************

Description:

Field userMapper in worldtolingyidianke.file.service.impl.UserServiceImpl required a bean of type 'worldtolingyidianke.file.mappers.UserMapper' that could not be found.

The injection point has the following annotations:

   - @org.springframework.beans.factory.annotation.Autowired(required=true)

经过细心的推敲，终于找到问题引起的原因：Mapper映射这里必须要添加@Mapper注解

添加注解之后，发现不再报错了