设计模式-享元模式

Author: dolyw

DesignPattern/src/main/java/com/design/flyweight/ConcreteFlyweight.java

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+package com.design.flyweight;
+
+/**
+ * 具体享元
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2022/1/24 14:12
+ */
+public class ConcreteFlyweight implements Flyweight {
+
+    private String key;
+
+    public ConcreteFlyweight(String key) {
+        this.key = key;
+    }
+
+    @Override
+    public void handle(UnsharableFlyweight unsharableFlyweight) {
+        System.out.println(this.key + "被调用，非享元信息:" + unsharableFlyweight.getMsg());
+    }
+}

DesignPattern/src/main/java/com/design/flyweight/Flyweight.java

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+package com.design.flyweight;
+
+/**
+ * 抽象享元
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2022/1/24 14:12
+ */
+public interface Flyweight {
+
+    /**
+     * 处理方法
+     *
+     * @param unsharableFlyweight
+     * @return void
+     * @throws
+     * @author wliduo[i@dolyw.com]
+     * @date 2022/1/24 14:15
+     */
+    void handle(UnsharableFlyweight unsharableFlyweight);
+
+}

DesignPattern/src/main/java/com/design/flyweight/FlyweightFactory.java

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+package com.design.flyweight;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * 享元工厂
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2022/1/24 14:15
+ */
+public class FlyweightFactory {
+
+    private Map<String, Flyweight> flyweightMap = new HashMap<>(16);
+
+    /**
+     * 工厂根据key获取Flyweight
+     *
+     * @param key
+     * @return com.design.flyweight.Flyweight
+     * @throws
+     * @author wliduo[i@dolyw.com]
+     * @date 2022/1/24 14:19
+     */
+    public Flyweight getFlyweight(String key) {
+        Flyweight flyweight = flyweightMap.get(key);
+        if (flyweight == null) {
+            flyweight  = new ConcreteFlyweight(key);
+            flyweightMap.put(key, flyweight);
+            System.out.println(key + "不存在，进行创建");
+        } else {
+            System.out.println(key + "存在，成功获取");
+        }
+        return flyweight;
+    }
+
+}

DesignPattern/src/main/java/com/design/flyweight/Main.java

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+package com.design.flyweight;
+
+/**
+ * 享元模式
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2022/1/24 13:44
+ */
+public class Main {
+
+    public static void main(String[] args) {
+        // 创建工厂
+        FlyweightFactory flyweightFactory = new FlyweightFactory();
+        // 使用工厂创建3个apple，2个banana对象
+        Flyweight apple1 = flyweightFactory.getFlyweight("apple");
+        Flyweight apple2 = flyweightFactory.getFlyweight("apple");
+        Flyweight apple3 = flyweightFactory.getFlyweight("apple");
+        Flyweight banana1 = flyweightFactory.getFlyweight("banana");
+        Flyweight banana2 = flyweightFactory.getFlyweight("banana");
+        // 使用不同的对象处理发现使用的其实是同一个
+        apple1.handle(new UnsharableFlyweight("第1次处理apple"));
+        apple2.handle(new UnsharableFlyweight("第2次处理apple"));
+        apple3.handle(new UnsharableFlyweight("第3次处理apple"));
+        banana1.handle(new UnsharableFlyweight("第1次处理banana"));
+        banana2.handle(new UnsharableFlyweight("第2次处理banana"));
+    }
+
+}

DesignPattern/src/main/java/com/design/flyweight/UnsharableFlyweight.java

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+package com.design.flyweight;
+
+/**
+ * 非享元角色
+ *
+ * @author wliduo[i@dolyw.com]
+ * @date 2022/1/24 14:14
+ */
+public class UnsharableFlyweight {
+
+    private String msg;
+
+    public UnsharableFlyweight(String msg) {
+        this.msg = msg;
+    }
+
+    public String getMsg() {
+        return msg;
+    }
+}