ADD file via upload

AdMapper.java

@@ -0,0 +1,10 @@
+package com.gk.study.mapper;
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import com.gk.study.entity.Ad;
+import org.apache.ibatis.annotations.Mapper;
+
+@Mapper
+public interface AdMapper extends BaseMapper<Ad> {
+
+}