Go4Expert - How to prevent your class getting inherited

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How to prevent your class getting inherited

When you plan to design a Class for which you feel that it should not be inherited further by any other class then...Here is a tip : Use of Virtual Private Inheritance

Code:

#include <iostream>



using namespace std;



class Base

{

  protected:

    Base()

    {

      cout<<"Base::Base"<<endl;

    }

};



class Dervied : virtual private Base

{

  public:

     Dervied()

     {

       cout<<"Dervied::Dervied"<<endl;

     }

};



class Client : public Dervied

{

  public:

     Client()

     {

       cout<<"Client::Client"<<endl;

     }

};



int main(void)

{

  Client c;

  return 0;

}

Here Derived class cannot be inherited by any other class.But when our client class tries to inherit we get a Error :
In constructor `Client::Client()':
error: `Base::Base()' is protected

The reason is simple when ever you inherit a class virtually then you should call the constructor of Base explicity on good design.

Re: How to prevent your class getting inherited

Nice one...
You can also get this concept in this thread
http://www.go4expert.com/showthread.php?t=8278

Re: How to prevent your class getting inherited

Nominate this article for Article of the month for February 2009

Re: How to prevent your class getting inherited

Vote for this article for Article of the month February 2009