Is there a difference between calling a supermethod and not implementing?

Question

In the following example, the call FirstChildclass first; first.someMethod(); will do the same as SecondChildclass second; second.someMethod();. Or am I wrong?

class Superclass {
   public void someMethod() {
      //do something
   }
}

class FirstChildclass extends Superclass {

   @Override
   public void someMethod() {
      super.someMethod();
   }

   public void someOtherMethod() {
      //do something else
   }
}

class SecondChildclass extends Superclass {

   public void someOtherMethod() {
      //do something else
   }
}

Is there a reason why one will implement it like in FirstChildclass? Because I have seen many implementations like in FistChildclass and am wondering why anyone would do it.

That is exactly the question. If I just want the logic of super method. Why would I write it in the way of `FirstChildclass`? — emi-le, Oct 04 '16 at 12:36
Possible duplicate of [When NOT to call super() method when overriding?](http://stackoverflow.com/questions/10244785/when-not-to-call-super-method-when-overriding) — R. Zagórski, Oct 04 '16 at 12:38
I can only guess. It is code generated using code generation / refactoring functionality of an IDE; it is not the product of actual thought. — Gimby, Oct 04 '16 at 12:40
dude, in your question you even hasn't any inheritance between your classes :( so this code will not compile — Sergey Frolov, Oct 04 '16 at 12:46

xenteros · Accepted Answer · 2016-10-04T12:41:31.707

3

If you ask about the difference between:

@Override
public returnType someName() {
    return super.someName();
}

and not overriding it. There is no difference as well as there is no sense in doing it.

You should call super.someName() just in case you want to extend the original method.

Watch out! If you have a constructor you want to use in a child class, but you don't need any additional behavior, you'll call super(arguments).

edited Oct 04 '16 at 12:41

answered Oct 04 '16 at 12:37

xenteros

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void method can't return anything – Sergey Frolov Oct 04 '16 at 12:40
TY, xenteros. I was of the same opinion, but wanted to be sure. – emi-le Oct 04 '16 at 13:35

Thusitha Thilina Dayaratne · Answer 2 · 2016-10-04T13:28:20.970

2

This is about your design. Override means you wanna change the already existing implementation which is inherited from the parent. If you are not doing anything different then you don;t want to do the

@Override
public void someMethod() {
      super.someMethod();
}

That is useless.

@Override
public void someMethod() {
   // do some other logic
   super.someMethod();
   // do some other logic
}

This is perfectly ok :) Because you are doing some tasks other than the parent's implementation.

edited Oct 04 '16 at 13:28

answered Oct 04 '16 at 12:41

Thusitha Thilina Dayaratne

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why i get -1 for this? – Thusitha Thilina Dayaratne Oct 04 '16 at 12:43
This is correct. However, be aware that this can sometimes be a sign of poor design (in the base class or derived class or both). – Klitos Kyriacou Oct 04 '16 at 12:52
Yeah I agree, this might lose the original concept of override – Thusitha Thilina Dayaratne Oct 04 '16 at 12:53
1

`unless parent class is abstract and the method is abstract.`---better delete this part. It might be the reason for the downvote. – Marko Topolnik Oct 04 '16 at 13:25

Is there a difference between calling a supermethod and not implementing?

2 Answers2