学步园

package com.lyklinse;</p> <p>/**<br /> * <p>Title: </p><br /> *<br /> * <p>Description: </p><br /> *<br /> * <p>Copyright: Copyright (c) 2009</p><br /> *<br /> * <p>Company: </p><br /> *<br /> * @author not attributable<br /> * @version 1.0<br /> */<br /> public class DecoratorPatterns {<br /> public DecoratorPatterns() {<br /> }</p> <p> public static void main(String[] args) {<br /> DecoratorPatterns decoratorpatterns = new DecoratorPatterns();<br /> CoffeeShop2 coffee = new CoffeeShop2();<br /> coffee.testCappuccino();<br /> coffee.testCafeMocha();<br /> }<br /> }</p> <p>interface DrinkComponent {<br /> String getDescription();</p> <p> float getTotalCost();<br /> }</p> <p>class Mug implements DrinkComponent {<br /> public String getDescription() {<br /> return "mug";<br /> }</p> <p> public float getTotalCost() {<br /> return 0;<br /> }<br /> }</p> <p>abstract class Decorator implements DrinkComponent {<br /> protected DrinkComponent component;<br /> Decorator(DrinkComponent component) {<br /> this.component = component;<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost();<br /> }</p> <p> public abstract String getDescription();<br /> }</p> <p>class Espresso extends Decorator {<br /> private float cost = 0.75f;<br /> private String description = " espresso";<br /> public Espresso(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost() + cost;<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class Decaf extends Decorator {<br /> private String description = " decaf";<br /> public Decaf(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class FoamedMilk extends Decorator {<br /> private float cost = 0.25f;<br /> private String description = " foamed milk";<br /> public FoamedMilk(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost() + cost;<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class SteamedMilk extends Decorator {<br /> private float cost = 0.25f;<br /> private String description = " steamed milk";<br /> public SteamedMilk(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost() + cost;<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class Whipped extends Decorator {<br /> private float cost = 0.25f;<br /> private String description = " whipped cream";<br /> public Whipped(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost() + cost;<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class Chocolate extends Decorator {<br /> private float cost = 0.25f;<br /> private String description = " chocolate";<br /> public Chocolate(DrinkComponent component) {<br /> super(component);<br /> }</p> <p> public float getTotalCost() {<br /> return component.getTotalCost() + cost;<br /> }</p> <p> public String getDescription() {<br /> return component.getDescription() +<br /> description;<br /> }<br /> }</p> <p>class CoffeeShop2 {<br /> public void testCappuccino() {<br /> // This just makes sure it will complete<br /> // without throwing an exception.<br /> // Create a plain cappucino<br /> DrinkComponent cappuccino = new Espresso(new FoamedMilk(new Mug()));<br /> System.out.println(cappuccino.<br /> getDescription().trim() + ": $" +<br /> cappuccino.getTotalCost());<br /> }</p> <p> public void testCafeMocha() {<br /> // This just makes sure it will complete<br /> // without throwing an exception.<br /> // Create a decaf cafe mocha with whipped<br /> // cream<br /> DrinkComponent cafeMocha = new Espresso(<br /> new SteamedMilk(new Chocolate(new Whipped(<br /> new Decaf(new Mug())))));<br /> System.out.println(cafeMocha.getDescription().<br /> trim() + ": $" + cafeMocha.getTotalCost());<br /> }<br /> }<br />