Main.java

package pkg;

public class Main {

    public static void main(String[] args) {
        Dog d = new Dog();
        d.woof();
        d.scratch();

        Dog d1 = new AngryDog();
        d1.scratch();

        sayHello(d);
        sayHello(d1);

    }

    public static void sayHello(Animal d) {
        System.out.println("Hello");
        d.scratch();
    }

}

class Animal {

    private String name;

    public void scratch() {
        System.out.println("Scratch");
    }

    public String getName() {
        return name;
    }

}

class Dog extends Animal {

    public String furColour;

    public void woof(){
        System.out.println("Woof");
    }

}

class AngryDog extends Dog {

    @Override
    public void scratch() {
        System.out.println("OW");
    }
}

class Cat extends Animal {

    private String furColour;

    public void meow() {
        System.out.println("Meow");
    }

}