Initial commit: backend code

src/main/java/com/example/building/mapper/OrderMapper.java

@@ -0,0 +1,12 @@
+package com.example.building.mapper;
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import com.example.building.entity.Order;
+import org.apache.ibatis.annotations.Mapper;
+
+/**
+ * 订单Mapper接口
+ */
+@Mapper
+public interface OrderMapper extends BaseMapper<Order> {
+}