不同口味的咖啡

买不同口味的咖啡，学习中间的思想

Food

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:33
 */
public abstract class Food {
    //价格
    public abstract int cost();
}

Condiment

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:35
 */
public abstract class Condiment extends Food{
    //被添加的那个饮料
    protected Food drink;
}

Coffee

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:34
 */
public class Coffee extends Food{
    @Override
    public int cost() {
        return 40;
    }
}

Milk

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:41
 */
public class Milk extends Condiment{
    public Milk(Food drink) {
        this.drink = drink;
    }

    @Override
    public int cost() {
        return 10 + drink.cost();
    }
}

Sugar

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:38
 */
public class Sugar extends Condiment{
    public Sugar(Food drink) {
        this.drink = drink;
    }

    //总价格
    @Override
    public int cost() {
        return 1 + drink.cost();
    }
}

Tea

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:42
 */
public class Tea extends Condiment{
    public Tea(Food drink) {
        this.drink = drink;
    }

    //总价格
    @Override
    public int cost() {
        return 5 + drink.cost();
    }
}

Main

package decorator;

/**
 * @version 1.0
 * @date 2021/10/12 17:43
 */
public class Main {
    public static void main(String[] args) {
        Food coffee = new Coffee();
        Food milk = new Milk(new Sugar(new Tea(new Coffee())));
        System.out.println(coffee.cost());
        System.out.println(milk.cost());
    }
}

装饰者模式设计思想，在IO流中使用过。