Hello,

class SuperClass {
    public void printA() { System.out.println("Super class"); }
    public void displayDotts() { System.out.println("#########"); }
}
class SubClass extends SuperClass {
    public void printA() { System.out.println("Sub class");    }
    public void displayDotts() { System.out.println("............."); }
}
public class OverrideDemo {
    public static void main(String[] args) {
        SuperClass s1 = new SubClass();
        s1.printA();
        s1.displayDotts();
    }
}

1. Why does s1.printA() statement trigger SubClass's printA function
instead of SuperClass's printA function, as I declared of type
"SuperClass" eventhough referenced to "SubClass"?
2. Buf if I delete SubClass's printA function, how could SuperClass's
printA function being triggered?
3. Why does compilation error occurs if I delete SuperClass's  printA
function?

Thanks for the answer.