添加注释

Signed-off-by: 周晓航 <xiaohang.zhou@freemud.com>

shopping-cart-application-service/src/main/java/cn/freemud/service/delivery/impl/GradDeliveryServiceImpl.java

@@ -205,7 +205,7 @@ public class GradDeliveryServiceImpl extends AbstractDeliveryServiceImpl impleme
         if (new BigDecimal(riderDistance).compareTo(new BigDecimal(defaultDeliveryRange)) <= 0) {
             return deliveryAmount;
         } else {
-            //计算实际配送费
+            //计算实际配送费  (总距离-基础配送距离)/每公里增加基数*每公里配送加钱 + 基础配送费
             BigDecimal extraAmount = (new BigDecimal(riderDistance).subtract(new BigDecimal(defaultDeliveryRange)))
                     .divide(new BigDecimal(addRangeCount), 0, BigDecimal.ROUND_UP)
                     .multiply(new BigDecimal(addRangeAmount));