Java inheritance method call

Question

I have a interesting scenario that.

public class Base {

    public void hello(){
        this.say();
        System.out.println("hello-Base");
    }

    protected void say(){
        System.out.println("say-Base");
    }
}



public class Derived extends Base {

    public Derived(){
        super.hello();      
    }

    public static void main(String[] args) {
        Derived d = new Derived();      
    }

    public void say(){
        System.out.println("say-Derived");
    }

}

The output given is that:

say-Derived
hello-Base

I was expecting that when super.hello() method was invoked, say() method of Base classes was invoked rather than say()method of Derived class.

What is the reason behind this logic?

this is a Derived

assylias
– assylias

2012-12-04 09:46:45 +00:00
Commented Dec 4, 2012 at 9:46 — assylias
– assylias, Commented Dec 4, 2012 at 9:46

Abhishek_Mishra · Accepted Answer · 2012-12-04 09:50:15Z

2

Super.hello() calls this.say() which(this) refer to the current object i.e. derived so it calls the say method of derived class.

answered Dec 4, 2012 at 9:50

Abhishek_Mishra

4,6315 gold badges28 silver badges39 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Narendra Pathai · Accepted Answer · 2012-12-04 09:55:42Z

1

Because this -- points to ---> Instance of Type Derived

So due to overriding Derived class method is called.

answered Dec 4, 2012 at 9:55

Narendra Pathai

42.1k18 gold badges88 silver badges122 bronze badges

Comments

Vallabh Patade · Accepted Answer · 2012-12-04 09:58:14Z

1

super.hello(); is raised from Derived constructor i.e. object of derived class. Which in turns calls this.say() i.e. derived.say(). So that's why the output is so.

answered Dec 4, 2012 at 9:58

Vallabh Patade

5,1306 gold badges35 silver badges41 bronze badges

Collectives™ on Stack Overflow

Java inheritance method call

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related