Decorator 예제

 

 

public class Main {
    public static void main(String[] args) {
        Beverage espresso = new Espresso();
        espresso = new Milk(espresso);
        espresso = new Moka(espresso);

        System.out.println(espresso.cost());
        System.out.println(espresso.getDescription());
    }
}

public abstract class Beverage {
    protected String description = "empty";

    public String getDescription() {
        return description;
    }

    public abstract int cost();
}

public class Espresso extends Beverage {
    public Espresso() {
        description = "Espresso";
    }

    public int cost() {
        return 10;
    }
}

public abstract class CondimentDecorator extends Beverage {
    Beverage beverage;
    public abstract String getDescription();
}

public class Milk extends CondimentDecorator {
    public Milk(Beverage beverage) {
        this.beverage = beverage;
    }

    @Override
    public String getDescription() {
        return beverage.getDescription() + " + Milk";
    }

    @Override
    public int cost() {
        return beverage.cost() + 5;
    }
}

public class Moka extends CondimentDecorator {
    public Moka(Beverage beverage) {
        this.beverage = beverage;
    }

    @Override
    public String getDescription() {
        return beverage.getDescription() + " + Moka";
    }

    @Override
    public int cost() {
        return beverage.cost() + 3;
    }
}

 

18
Espresso + Milk + Moka

 

 

 

https://jusungpark.tistory.com/9?category=630296 

디자인패턴 - 데코레이터 패턴 (decorator pattern)