/**
 * 饮品.
 *
 * @author jialin.li
 * @date 2019-12-26 22:58
 */
public interface Beverage {
    /** 获取描述 */
    String getDescription();
    /** 获取金额 */
    double getPrice();
}

/**
 * 咖啡豆1
 *
 * @author jialin.li
 * @date 2019-12-26 22:59
 */
public class CoffeeBean1 implements Beverage {

    @Override
    public String getDescription() {
        return "第一种咖啡豆";
    }

    @Override
    public double getPrice() {
        return 10d;
    }
}

/**
 * 咖啡豆2
 *
 * @author jialin.li
 * @date 2019-12-26 23:00
 */
public class CoffeeBean2 implements Beverage{
    @Override
    public String getDescription() {
        return "第一种咖啡豆";
    }

    @Override
    public double getPrice() {
        return 12.5d;
    }
}

/**
 * 装饰器.
 *
 * @author jialin.li
 * @date 2019-12-26 23:02
 */
public class Decorator implements Beverage{

    protected Beverage coffee;

    @Override
    public String getDescription() {
        return "装饰器，由子类重写方法";
    }

    @Override
    public double getPrice() {
        return 0;
    }
}

/**
 * 蜂蜜.
 *
 * @author jialin.li
 * @date 2019-12-26 23:07
 */
public class Honey extends Decorator {
    public Honey(Beverage coffee) {
        this.coffee = coffee;
    }

    @Override
    public String getDescription() {
        return coffee.getDescription() + "加蜂蜜";
    }

    @Override
    public double getPrice() {
        return coffee.getPrice() + 4.5d;
    }
}

/**
 * 牛奶.
 *
 * @author jialin.li
 * @date 2019-12-26 23:03
 */
public class Milk extends Decorator {
    public Milk(Beverage coffee) {
        this.coffee = coffee;
    }

    @Override
    public String getDescription() {
        return coffee.getDescription() + "加牛奶";
    }

    @Override
    public double getPrice() {
        return coffee.getPrice() + 1.5d;
    }
}

/**
 * 摩卡.
 *
 * @author jialin.li
 * @date 2019-12-26 23:05
 */
public class Mocha extends Decorator {
    public Mocha(Beverage coffee) {
        this.coffee = coffee;
    }

    @Override
    public String getDescription() {
        return coffee.getDescription() + "加摩卡";
    }

    @Override
    public double getPrice() {
        return coffee.getPrice() + 2.5d;
    }
}

/**
 * 测试类.
 *
 * @author jialin.li
 * @date 2019-12-26 23:09
 */
public class Main {
    public static void main(String[] args) {
        CoffeeBean1 coffee1 = new CoffeeBean1();
        CoffeeBean2 coffee2 = new CoffeeBean2();

        // 加蜂蜜
        Beverage honey = new Honey(coffee1);
        // 加摩卡
        Beverage mocha = new Mocha(honey);
        System.out.println(mocha.getDescription());
        System.out.println(mocha.getPrice());

        // 加牛奶
        Milk milk = new Milk(coffee2);
        System.out.println(milk.getDescription());
        System.out.println(milk.getPrice());
    }
}