Private Final Method

[gaurav gupta sitm]

import java.util.*;
public class MainClass {

private final void a(){System.out.println("ocpjp");}

class B extends MainClass{private final void a(){a();} } 
     public static void main(String args[]){
MainClass a =new MainClass().new B();
a.a();
  }
}
  

Why this code overide final method ? How it can be possible to overide final method ?
IF you want say a() method in MainClass use private modifier so hiden from B . If it is hiden so how can it print "ocpjp" by calling method a() of MainClass from method a() of B class.

[Cole Tarbet]

You're right! I just compiled that code and got "ocpjp". NetBeans does warn about it being pointless to mark a private method final....

I'm thinking that the private modifier hides the original method which means that class B can redefine it without overriding the original. Thanks for bringing this up. I know I learned something.

http://www.javaworld.com/javaworld/javaqa/2000-09/02-qa-0915-private.html

============================================================

I couldn't resist making a small change...

public static void main(String args[]) {
        B a = new Main().new B();
        a.a();
    }

Exception in thread "main" java.lang.StackOverflowError

[nitin sethi]

gaurav gupta sitm wrote:

import java.util.*;
public class MainClass {

private final void a(){System.out.println("ocpjp");}

class B extends MainClass{private final void a(){a();} } 
     public static void main(String args[]){
MainClass a =new MainClass().new B();
a.a();
  }
}
  

Why this code overide final method ? How it can be possible to overide final method ?
IF you want say a() method in MainClass use private modifier so hiden from B . If it is hiden so how can it print "ocpjp" by calling method a() of MainClass from method a() of B class.

Gaurav,

A method marked either private or final can't be overridden as that method is not inherited by the subclass.

I just tried the below code and I can see the overriding hasn't happened.

import java.util.*;
public class MainClass {

    private final void a(){
        System.out.println("ocpjp");
    }

    class B extends MainClass{
        private final void a(){
            System.out.println("ocpjp_another");
            MainClass.this.a();
        } 
    } 

    public static void main(String args[]){
        MainClass a =new MainClass().new B();
        a.a();
        B b = new MainClass().new B();
        b.a();
    }
}

[Ogeh Ikem]

Using the @Override annotation allows you to verify that a method has truly been overridden.

[O. Ziggy]

gaurav gupta sitm wrote:

import java.util.*;
public class MainClass {

private final void a(){System.out.println("ocpjp");}

class B extends MainClass{private final void a(){a();} } 
     public static void main(String args[]){
MainClass a =new MainClass().new B();
a.a();
  }
}
  

Why this code overide final method ? How it can be possible to overide final method ?
IF you want say a() method in MainClass use private modifier so hiden from B . If it is hiden so how can it print "ocpjp" by calling method a() of MainClass from method a() of B class.

Is there an extra closing curly brace on line six?

[Scotty Mitchell]

Is there an extra closing curly brace on line six?

Nah, the method a() of class B has a method body that's why there is another curly brace there. Hard to see definitely lol

So the method a() in class B is not overriding the method a() in MainClass. As was stated above, you arn't overriding a method if it is private you are rewriting a NEW method with the same name. Private methods arn't inherited by the subclass. The call that you are making is not going to class B's a() method at all. Put a print statement in there and see. If you change the call to be cast to a B type you will get a stack overflow because you are continuously calling the same method over and over again.

[Seetharaman Venkatasamy]

private methods are implicitly final . so making a private method as final is redundant!.