springboot Invalid bound statement (not found)

如下图所示：必须添加上dao，否则加载不进来，会报

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.july.data.service.UserService.getUserInfo

如果路径不存在，会报：

Field userMapper in com.july.data.service.UserServiceImpl required a bean of type 'com.july.data.dao.UserMapper' that could not be found.