Question

Assume Superis the name of a superclass and Subis the name of a subclass. If we have:

Super s = new Sub();

we can only invoke the methods defined in Super class, and we cannot access the methods added by the Sub class. Is this statement true or false?

A. true

B. false

I appreciate if you put some descritions

Answer 1

Answer:

This statement is FALSE. To prove it, I am giving you the below code and the screenshot, so that it is clear to you.

Super.java

public class Super {

    public void method1(){ // method has just a simple print statement

        System.out.println("method1() from base");

    }

}

SubClass.java

public class SubClass extends Super {

    public void method1(){ // this method is also declared in Super class

        System.out.println("method1() from derived");

    }

}

TestDerived.java

public class TestDerived {
    public static void main(String [] args){

        Super s = new SubClass();
        s.method1(); // method of SubClass gets called

    }
}

Good Luck!!! Thank you