本篇随笔主要介绍用Java实现简单的装饰器设计模式：
先来看一下装饰器设计模式的类图：
从图中可以看到，我们可以装饰Component接口的任何实现类，而这些实现类也包括了装饰器本身，装饰器本身也可以再被装饰。
下面是用Java实现的简单的装饰器设计模式，提供的是从基本的加入咖啡入手，可以继续加入牛奶，巧克力，糖的装饰器系统。
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interface Component { void method();}class Coffee implements Component { @Override public void method() { // TODO Auto-generated method stub System.out.println("倒入咖啡"); } }class Decorator implements Component { public Component comp; public Decorator(Component comp) { this.comp = comp; } @Override public void method() { // TODO Auto-generated method stub comp.method(); } }class ConcreteDecorateA extends Decorator { public Component comp; public ConcreteDecorateA(Component comp) { super(comp); this.comp = comp; } public void method1() { System.out.println("倒入牛奶"); } public void method2() { System.out.println("加入糖 "); } public void method() { super.method(); method1(); method2(); }}class ConcreteDecorateB extends Decorator { public Component comp; public ConcreteDecorateB(Component comp) { super(comp); this.comp = comp; } public void method1() { System.out.println("加入巧克力"); } public void method() { super.method(); method1(); }}public class TestDecoratePattern { public static void main(String[] args) { Component comp = new Coffee(); comp.method(); System.out.println("--------------------------------------------------"); Component comp1 = new ConcreteDecorateA(comp); comp1.method(); System.out.println("--------------------------------------------------"); Component comp2 = new ConcreteDecorateB(comp1); comp2.method(); System.out.println("--------------------------------------------------"); Component comp3 = new ConcreteDecorateB(new ConcreteDecorateA(new Coffee())); comp3.method(); System.out.println("--------------------------------------------------"); Component comp4 = new ConcreteDecorateA(new ConcreteDecorateB(new Coffee())); comp4.method(); }} |
运行结果：
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
