通用Mapper环境下，mapper接口无法注入问题

写了一个mapper接口

package com.nyist.mapper;

import com.nyist.entity.User;
import tk.mybatis.mapper.common.Mapper;

public interface UserMapper extends Mapper<User> {

}

在Service中注入该接口--启动项目，报错一气呵成😢

Unsatisfied dependency expressed through field 'userMapper'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.nyist.mapper.UserMapper' available:Unsatisfied dependency expressed through field 'userMapper'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.nyist.mapper.UserMapper' available:

查看springboot启动类，

import tk.mybatis.spring.annotation.MapperScan;
@MapperScan("com.nyist.mapper")
.............

ok