问题描述：
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Tue Aug 20 15:30:12 CST 2019
There was an unexpected error (type=Internal Server Error, status=500).
Invalid bound statement (not found): com.example.mapper.UserMapper.getAllUser
解决方法：
之前的错误地址改正确即可