Description or Example
# 核心代码
## 特别说明
> 如果没有订单状态, 即这个订单根本不存在
```java
@RequestMapping("/orderStatus/{orderSn}")
public R getOrderStatus(@PathVariable String orderSn) {
Integer status = orderService.getStatusBySn(orderSn);
return R.ok().setData(status);
}
```
```java
@Override
public Integer getStatusBySn(String orderSn) {
LambdaQueryWrapper<OrderEntity> queryWrapper = new LambdaQueryWrapper<>();
queryWrapper.select(OrderEntity::getStatus).eq(OrderEntity::getOrderSn, orderSn);
OrderEntity orderEntity = this.baseMapper.selectOne(queryWrapper);
return orderEntity != null ? orderEntity.getStatus() : null;
}
```