Chương 4-Bài 8. Đa hình (Polymorphism)

Đa hình (Polymorphism)

Ví dụ

class Animal {
  public void animalSound() {
    System.out.println("The animal makes a sound");
  }
}

class Cat extends Animal {
  public void animalSound() {
    System.out.println("The cat says: meow!");
  }
}

class Dog extends Animal {
  public void animalSound() {
    System.out.println("The dog says: woof!");
  }
}

class Cow extends Animal {
  public void animalSound() {
    System.out.println("The cow says: moo!");
  }
}

class Main {
  public static void main(String[] args) {
    Animal myAnimal = new Animal();  // Create a Animal object
    Animal myCat = new Cat();  // Create a Cat object
    Animal myDog = new Dog();  // Create a Dog object
    Animal myCow = new Cow();  // Create a Cow object
    myAnimal.animalSound();
    myCat.animalSound();
    myDog.animalSound();
    myCow.animalSound();
  }
}