package com.jmj.pattern.decorator;
/**
* 快餐类(抽象构建角色)
*/
public abstract class FastFood {
private float price;
private String desc;
public float getPrice() {
return price;
}
public void setPrice(float price) {
this.price = price;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
public FastFood() {
}
public FastFood(float price, String desc) {
this.price = price;
this.desc = desc;
}
public abstract float cost();
}
package com.jmj.pattern.decorator;
/**
* 炒面(具体的构件角色 )
*/
public class FriedNoodles extends FastFood{
public FriedNoodles() {
super(12,"炒面");
}
@Override
public float cost() {
return getPrice();
}
}
package com.jmj.pattern.decorator;
public class FriedRice extends FastFood{
public FriedRice() {
super(10,"炒饭");
}
@Override
public float cost() {
return getPrice();
}
}
package com.jmj.pattern.decorator;
/**
* 装饰者类(抽象装饰者角色)
*/
public abstract class Garnish extends FastFood{
//声明快餐类的变量
private FastFood fastFood;
public FastFood getFastFood() {
return fastFood;
}
public void setFastFood(FastFood fastFood) {
this.fastFood = fastFood;
}
public Garnish(FastFood fastFood,float price, String desc) {
super(price, desc);
this.fastFood = fastFood;
}
}
package com.jmj.pattern.decorator;
/**
* 鸡蛋类 (具体的装饰者角色)
*/
public class Egg extends Garnish{
public Egg(FastFood fastFood) {
super(fastFood, 1, "鸡蛋");
}
@Override
public float cost() {
//计算价格
return getPrice()+getFastFood().cost();
}
@Override
public String getDesc() {
return super.getDesc()+getFastFood().getDesc();
}
}
package com.jmj.pattern.decorator;
/**
* 鸡蛋类 (具体的装饰者角色)
*/
public class Bacon extends Garnish{
public Bacon(FastFood fastFood) {
super(fastFood, 2, "培根");
}
@Override
public float cost() {
//计算价格
return getPrice()+getFastFood().cost();
}
@Override
public String getDesc() {
return super.getDesc()+getFastFood().getDesc();
}
}
package com.jmj.pattern.decorator;
public class Client {
public static void main(String[] args) {
//点一份炒饭
FastFood friedRice = new FriedRice();
System.out.println(friedRice.getDesc()+" "+friedRice.cost()+"元");
System.out.println("============");
//在上面的炒饭中加一个鸡蛋
friedRice=new Egg(friedRice);
friedRice=new Egg(friedRice);
System.out.println(friedRice.getDesc()+" "+friedRice.cost()+"元");
friedRice = new Bacon(friedRice);
System.out.println(friedRice.getDesc()+" "+friedRice.cost()+"元");
}
}
其实就是 装饰者类 继承了 原本的 父抽象类,又聚合了 父抽象类