策略模式

Author: CPU-Code

pattern/README.md

@@ -117,7 +117,6 @@
 - [x] [策略模式](src/main/java/com/cpucode/pattern/strategy/promotion/PromotionActivityTest2.java)
 - [x] [策略模式](src/main/java/com/cpucode/pattern/strategy/promotion/PromotionActivityTest3.java)
 - [x] [策略模式](src/main/java/com/cpucode/pattern/strategy/pay/PayStrategyTest.java)
-- [x] [策略模式](src/main/java/com/cpucode/pattern/strategy/promotion/PromotionActivityTest3.java)
 
 ## [模板模式]()
 

pattern/src/main/java/com/cpucode/pattern/strategy/pay/Order.java

@@ -0,0 +1,42 @@
+package com.cpucode.pattern.strategy.pay;
+
+import com.cpucode.pattern.strategy.pay.payport.PayState;
+import com.cpucode.pattern.strategy.pay.payport.PayStrategy;
+import com.cpucode.pattern.strategy.pay.payport.Payment;
+
+/**
+ * @author : cpucode
+ * @date : 2021/6/1
+ * @time : 23:11
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class Order {
+    private String uid;
+    private String orderId;
+    private double amount;
+
+    public Order(String uid,String orderId,double amount){
+        this.uid = uid;
+        this.orderId = orderId;
+        this.amount = amount;
+    }
+
+    /**
+     * 完美地解决了 switch 的过程， 不需要在代码逻辑中写 switch 了
+     *  更不需要写 if else if
+     * @return
+     */
+    public PayState pay(){
+        return pay(PayStrategy.DEFAULT_PAY);
+    }
+
+    public PayState pay(String payKey){
+        Payment payment = PayStrategy.get(payKey);
+
+        System.out.println("欢迎使用" + payment.getName());
+        System.out.println("本次交易金额为： " + amount + "， 开始扣款...");
+
+        return payment.pay(uid, amount);
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/PayStrategyTest.java

@@ -0,0 +1,26 @@
+package com.cpucode.pattern.strategy.pay;
+
+import com.cpucode.pattern.strategy.pay.payport.PayStrategy;
+
+/**
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:37
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class PayStrategyTest {
+    public static void main(String[] args) {
+        // 省略把商品添加到购物车， 再从购物车下单 , 直接从点单开始
+        Order order = new Order("1","20180311001000009",324.45);
+
+        /**
+         * 开始支付， 选择微信支付、 支付宝、 银联卡、 京东白条、 财付通
+         *   每个渠道它支付的具体算法是不一样的
+         *
+         * 基本算法固定的
+         *      这个值是在支付的时候才决定用哪个值
+         */
+        System.out.println(order.pay(PayStrategy.ALI_PAY));
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/AliPay.java

@@ -0,0 +1,22 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ * 支付宝
+ *
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:03
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class AliPay extends Payment {
+    @Override
+    public String getName() {
+        return "支付宝";
+    }
+
+    @Override
+    protected double queryBalance(String uid) {
+        return 900;
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/JDPay.java

@@ -0,0 +1,22 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ * 京东白条
+ *
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:04
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class JDPay extends Payment {
+    @Override
+    public String getName() {
+        return "京东白条";
+    }
+
+    @Override
+    protected double queryBalance(String uid) {
+        return 500;
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/PayState.java

@@ -0,0 +1,28 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ *  支付完成以后的状态
+ *
+ * @author : cpucode
+ * @date : 2021/6/1
+ * @time : 23:12
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class PayState {
+    private int code;
+    private Object data;
+    private String msg;
+
+    public PayState(int code, String msg,Object data) {
+        this.code = code;
+        this.data = data;
+        this.msg = msg;
+    }
+
+    @Override
+    public String toString(){
+        return ("支付状态： [" + code + "]," + msg + ",交易详情： " + data);
+    }
+
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/PayStrategy.java

@@ -0,0 +1,39 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * 支付策略管理
+ *
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:29
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class PayStrategy {
+    public static final String ALI_PAY = "AliPay";
+    public static final String JD_PAY = "JdPay";
+    public static final String UNION_PAY = "UnionPay";
+    public static final String WECHAT_PAY = "WechatPay";
+    public static final String DEFAULT_PAY = ALI_PAY;
+
+    private static Map<String, Payment> payStrategy = new HashMap<String, Payment>();
+
+    static {
+        payStrategy.put(ALI_PAY,new AliPay());
+        payStrategy.put(WECHAT_PAY,new WechatPay());
+        payStrategy.put(UNION_PAY,new UnionPay());
+        payStrategy.put(JD_PAY,new JDPay());
+    }
+
+    public static Payment get(String payKey){
+        if(!payStrategy.containsKey(payKey)){
+            return payStrategy.get(DEFAULT_PAY);
+        }
+
+        return payStrategy.get(payKey);
+    }
+
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/Payment.java

@@ -0,0 +1,39 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ * 支付渠道
+ *
+ * @author : cpucode
+ * @date : 2021/6/1
+ * @time : 23:11
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public abstract class Payment {
+    /**
+     * 支付类型
+     * @return
+     */
+    public abstract String getName();
+
+    /**
+     * 查询余额
+     * @param uid
+     * @return
+     */
+    protected abstract double queryBalance(String uid);
+
+    /**
+     * 扣款支付
+     * @param uid
+     * @param amount
+     * @return
+     */
+    public PayState pay(String uid, double amount) {
+        if(queryBalance(uid) < amount){
+            return new PayState(500, "支付失败", "余额不足");
+        }
+
+        return new PayState(200, "支付成功", "支付金额： " + amount);
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/UnionPay.java

@@ -0,0 +1,22 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ * 银联支付
+ *
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:06
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class UnionPay extends Payment {
+    @Override
+    public String getName() {
+        return "银联支付";
+    }
+
+    @Override
+    protected double queryBalance(String uid) {
+        return 120;
+    }
+}

pattern/src/main/java/com/cpucode/pattern/strategy/pay/payport/WechatPay.java

@@ -0,0 +1,22 @@
+package com.cpucode.pattern.strategy.pay.payport;
+
+/**
+ * 微信支付
+ *
+ * @author : cpucode
+ * @date : 2021/6/2
+ * @time : 12:05
+ * @github : https://github.com/CPU-Code
+ * @csdn : https://blog.csdn.net/qq_44226094
+ */
+public class WechatPay extends Payment {
+    @Override
+    public String getName() {
+        return "微信支付";
+    }
+
+    @Override
+    protected double queryBalance(String uid) {
+        return 256;
+    }
+}