상속과 다형성

public class Animal {
    private String name;

    public Animal(String name) {
        this.name = name;
    }

    public String speak() {
        return name + ": ...?";
    }

    public String getName() { return name; }
}

class Dog extends Animal {
    public Dog(String name) {
        super(name);  // 부모 생성자 호출
    }

    @Override
    public String speak() {
        return getName() + ": 멍멍!";
    }
}

class Cat extends Animal {
    public Cat(String name) { super(name); }

    @Override
    public String speak() {
        return getName() + ": 야옹~";
    }
}

// 다형성 활용
Animal[] animals = { new Dog("뽀삐"), new Cat("나비") };
for (Animal a : animals) {
    System.out.println(a.speak());
}
// 뽀삐: 멍멍!
// 나비: 야옹~