Decorator Pattern

oop-in-spring/practice/design-pattern/decoratorPattern/Americano.java

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+package decoratorPattern;
+
+public class Americano extends Coffee {
+
+    @Override
+    public void brewing() {
+        System.out.println("Americano Coffee");
+    }
+}

oop-in-spring/practice/design-pattern/decoratorPattern/Coffee.java

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+package decoratorPattern;
+
+public abstract class Coffee {
+    public abstract void brewing();
+}

oop-in-spring/practice/design-pattern/decoratorPattern/Decorator.java

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+package decoratorPattern;
+
+// 여러가지 데코레이터의 상속 목적으로만 사용할 거라서 `abstract` class로 선언
+public abstract class Decorator extends Coffee {
+
+    Coffee coffee;
+
+    public Decorator(Coffee coffee) {
+        this.coffee = coffee;
+    }
+
+    @Override
+    public void brewing() {
+        coffee.brewing();
+    }
+}

oop-in-spring/practice/design-pattern/decoratorPattern/DecoratorMain.java

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+package decoratorPattern;
+
+import java.io.*;
+
+public class DecoratorMain {
+
+
+    public static void main(String[] args) throws FileNotFoundException {
+        Coffee coffee = new Americano();
+        coffee.brewing();
+
+        Coffee latteCoffee = new Latte(new Americano());
+        latteCoffee.brewing();
+
+        Coffee mochaCoffee = new Mocha(new Latte(new Americano()));
+        mochaCoffee.brewing();
+
+
+        Coffee whippedCreamCoffee = new WhippedCream(new Mocha(new Latte(new Americano())));
+        whippedCreamCoffee.brewing();
+
+        // 자바 API 속의 데코레이터 패턴
+        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream("a.out")));
+
+        /**
+         * public class FileInputStream extends InputStream {
+         *     public FileInputStream(String name) throws FileNotFoundException {
+         *         this(name != null ? new File(name) : null);
+         *     }
+         * }
+         */
+
+        /***
+         * public class InputStreamReader extends Reader {
+         *     public InputStreamReader(InputStream in) {
+         *         super(in);
+         *         sd = StreamDecoder.forInputStreamReader(in, this,
+         *                 Charset.defaultCharset()); // ## check lock object
+         *     }
+         * }
+         */
+
+        /**
+         * BufferedReader extends Reader {
+         *     public BufferedReader(Reader in) {
+         *         this(in, defaultCharBufferSize);
+         *     }
+         * }
+         */
+    }
+}

oop-in-spring/practice/design-pattern/decoratorPattern/Latte.java

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+package decoratorPattern;
+
+public class Latte extends Decorator {
+
+    public Latte(Coffee coffee) {
+        super(coffee);
+    }
+
+    @Override
+    public void brewing() {
+        super.brewing();
+        System.out.println("Adding Milk");
+    }
+}

oop-in-spring/practice/design-pattern/decoratorPattern/Mocha.java

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+package decoratorPattern;
+
+public class Mocha extends Decorator {
+
+    public Mocha(Coffee coffee) {
+        super(coffee);
+    }
+
+    @Override
+    public void brewing() {
+        super.brewing();
+        System.out.println("Adding Mocha syrup");
+    }
+}

oop-in-spring/practice/design-pattern/decoratorPattern/WhippedCream.java

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+package decoratorPattern;
+
+public class WhippedCream extends Decorator {
+
+    public WhippedCream(Coffee coffee) {
+        super(coffee);
+    }
+
+    @Override
+    public void brewing() {
+        super.brewing();
+        System.out.println("Adding Whipping Cream");
+    }
+}