策略模式，代码重构

Author: enjoyCoding666

pom.xml

@@ -18,6 +18,12 @@
             <artifactId>lombok</artifactId>
             <version>1.18.8</version>
         </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/strategy/demo/Client.java

@@ -0,0 +1,21 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:27
+ * @Description:
+ *
+ *  参考资料：https://www.cnblogs.com/ldsweely/p/12058346.html
+ */
+public class Client {
+
+    public static double getResult(long money, String type) {
+        MemberStrategy strategy = StrategyFactory.getInstance().getMemberStrategy(type);
+
+        if (strategy == null){
+            throw new IllegalArgumentException("please input right type");
+        }
+
+        return strategy.compute(money);
+    }
+}

src/main/java/strategy/demo/GoldStrategy.java

@@ -0,0 +1,20 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:06
+ * @Description:
+ */
+public class GoldStrategy implements MemberStrategy{
+
+    @Override
+    public double compute(long money) {
+        System.out.println("黄金会员 8折");
+        return money * 0.8;
+    }
+
+    @Override
+    public String getType() {
+        return UserTypeEnum.GOLD_VIP.getType();
+    }
+}

src/main/java/strategy/demo/MemberStrategy.java

@@ -0,0 +1,13 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:01
+ * @Description:
+ */
+public interface MemberStrategy {
+    // 计费方法
+    double compute(long money);
+
+    String getType();
+}

src/main/java/strategy/demo/OrdinaryStrategy.java

@@ -0,0 +1,20 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:02
+ * @Description:
+ */
+public class OrdinaryStrategy implements MemberStrategy {
+
+    @Override
+    public double compute(long money) {
+        System.out.println("普通会员 不打折");
+        return money;
+    }
+
+    @Override
+    public String getType() {
+        return UserTypeEnum.ORDINARY.getType();
+    }
+}

src/main/java/strategy/demo/PlatinumStrategy.java

@@ -0,0 +1,20 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:07
+ * @Description:
+ */
+public class PlatinumStrategy implements MemberStrategy {
+
+    @Override
+    public double compute(long money) {
+        System.out.println("白金会员 优惠50元，再打7折");
+        return (money - 50) * 0.7;
+    }
+
+    @Override
+    public String getType() {
+        return UserTypeEnum.PLATINUM_VIP.getType();
+    }
+}

src/main/java/strategy/demo/SilverStrategy.java

@@ -0,0 +1,20 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:04
+ * @Description:
+ */
+public class SilverStrategy implements MemberStrategy {
+
+    @Override
+    public double compute(long money) {
+        System.out.println("白银会员 优惠50元");
+        return money - 50;
+    }
+
+    @Override
+    public String getType() {
+        return UserTypeEnum.SILVER_VIP.getType();
+    }
+}

src/main/java/strategy/demo/StrategyFactory.java

@@ -0,0 +1,48 @@
+package strategy.demo;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:23
+ * @Description:
+ */
+public class StrategyFactory {
+
+    private Map<String, MemberStrategy> map;
+
+    public StrategyFactory() {
+
+        List<MemberStrategy> strategies = new ArrayList<>();
+
+        strategies.add(new OrdinaryStrategy());
+        strategies.add(new SilverStrategy());
+        strategies.add(new GoldStrategy());
+        strategies.add(new PlatinumStrategy());
+        strategies.add(new PlatinumStrategy());
+
+        // 重点
+        map = strategies.stream().collect(Collectors.toMap(MemberStrategy::getType, strategy -> strategy));
+
+        /* 等同上面
+        map = new HashMap<>();
+        for (Strategy strategy : strategies) {
+            map.put(strategy.getType(), strategy);
+        }*/
+    }
+
+    private static class Holder {
+        private static StrategyFactory instance = new StrategyFactory();
+    }
+
+    public static StrategyFactory getInstance() {
+        return Holder.instance;
+    }
+
+    public MemberStrategy getMemberStrategy(String type) {
+        return map.get(type);
+    }
+}

src/main/java/strategy/demo/UserTypeEnum.java

@@ -0,0 +1,42 @@
+package strategy.demo;
+
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\1\16 0016 23:08
+ * @Description:
+ */
+public enum UserTypeEnum {
+
+    ORDINARY("1","code1"),
+    SILVER_VIP("2","code2"),
+    GOLD_VIP("3","code3"),
+    PLATINUM_VIP("4","code4"),
+
+    ;
+
+
+    UserTypeEnum(String type, String code) {
+        this.type = type;
+        this.code = code;
+    }
+
+    private String type;
+    private String code;
+
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public String getCode() {
+        return code;
+    }
+
+    public void setCode(String code) {
+        this.code = code;
+    }
+}

src/main/java/strategy/AdvancedMemberStrategy.java renamed to src/main/java/strategy/demo2/AdvancedMemberStrategy.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 public class AdvancedMemberStrategy implements  MemberStrategy {
     @Override

src/main/java/strategy/Client.java renamed to src/main/java/strategy/demo2/Client.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 /**
  * 策略模式。针对不同等级的客户，采用不同的算法

src/main/java/strategy/IntermediateMemberStrategy.java renamed to src/main/java/strategy/demo2/IntermediateMemberStrategy.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 public class IntermediateMemberStrategy implements  MemberStrategy {
     @Override

src/main/java/strategy/MemberStrategy.java renamed to src/main/java/strategy/demo2/MemberStrategy.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 /**
  * 抽象折扣类

src/main/java/strategy/Price.java renamed to src/main/java/strategy/demo2/Price.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 public class Price {
     private  MemberStrategy strategy;

src/main/java/strategy/PrimaryMemberStrategy.java renamed to src/main/java/strategy/demo2/PrimaryMemberStrategy.java

@@ -1,4 +1,4 @@
-package strategy;
+package strategy.demo2;
 
 public class PrimaryMemberStrategy implements  MemberStrategy {
     @Override