Java-Abstract Class

//Abstract Class
abstract class AbstractComponent
{   
    //abstract method can be in abstract class
    protected int height,width;
    public abstract void paint();
    public void setSize(int w, int h)
    {
        height=h;
        width=w;
    }
}
class MyButton extends AbstractComponent
{
    public void paint()
    {
        System.out.println("Paint");
    }
}
class AbstractDemo
{
    public static void main(String[] args)
    {
        MyButton b1 = new MyButton();
        b1.setSize(500,500);
        b1.paint();

    }
}