Add1 (#140)

hcsp · Mar 23, 2020 · c1d573f · c1d573f
1 parent 34a50f0
commit c1d573f
Show file tree

Hide file tree

Showing 4 changed files with 22 additions and 21 deletions.
diff --git a/src/main/java/com/github/hcsp/polymorphism/Discount95Strategy.java b/src/main/java/com/github/hcsp/polymorphism/Discount95Strategy.java
@@ -1,3 +1,8 @@
 package com.github.hcsp.polymorphism;
 
-public class Discount95Strategy {}
+public class Discount95Strategy extends DiscountStrategy{
+    @Override
+    public int discount(int price, User user) {
+        return (int)(price * 0.95);
+    }
+}
diff --git a/src/main/java/com/github/hcsp/polymorphism/NoDiscountStrategy.java b/src/main/java/com/github/hcsp/polymorphism/NoDiscountStrategy.java
@@ -1,3 +1,8 @@
 package com.github.hcsp.polymorphism;
 
-public class NoDiscountStrategy {}
+public class NoDiscountStrategy extends DiscountStrategy{
+    @Override
+    public int discount(int price, User user) {
+        return price;
+    }
+}
diff --git a/src/main/java/com/github/hcsp/polymorphism/OnlyVipDiscountStrategy.java b/src/main/java/com/github/hcsp/polymorphism/OnlyVipDiscountStrategy.java
@@ -1,3 +1,8 @@
 package com.github.hcsp.polymorphism;
 
-public class OnlyVipDiscountStrategy {}
+public class OnlyVipDiscountStrategy extends DiscountStrategy{
+    @Override
+    public int discount(int price, User user) {
+        return user.isVip() ? (int) (price * 0.95) : price;
+    }
+}
diff --git a/src/main/java/com/github/hcsp/polymorphism/PriceCalculator.java b/src/main/java/com/github/hcsp/polymorphism/PriceCalculator.java
@@ -7,22 +7,8 @@ public class PriceCalculator {
     // OnlyVipDiscountStrategy 只有VIP打95折，其他人保持原价
     // 重构后的方法签名：
     // public static int calculatePrice(DiscountStrategy strategy, int price, User user)
-    public static int calculatePrice(String discountStrategy, int price, User user) {
-        switch (discountStrategy) {
-            case "NoDiscount":
-                return price;
-            case "Discount95":
-                return (int) (price * 0.95);
-            case "OnlyVip":
-                {
-                    if (user.isVip()) {
-                        return (int) (price * 0.95);
-                    } else {
-                        return price;
-                    }
-                }
-            default:
-                throw new IllegalStateException("Should not be here!");
-        }
+    public static int calculatePrice(DiscountStrategy strategy, int price, User user) {
+        return strategy.discount(price, user);
     }
-}
+
+}