Understanding Java Inheritance and function creation

Question

I have a base class which goes as below

class BaseClass{
  //this is a base class
  // I dont want to add any generic methods here as it is 
  //extended by tens of classes
}

Now Two particular classes which extends this base class

class Abc extends BaseClass{

//method
  void letsGo(){
    //this method is not there in base class
  }
}

class Xyz extends BaseClass{

//method
void letsGo(){
    //this method is not there in base class
  }

}

Now I need a function which have to accepts Class Xyz's object or Class Abc's object with a syntax similar to below

void run (BaseClass base){
  base.letsGo() // I know it wont work 
}

and call it like run(object of Abc) or run(object of Xyz) .

How do I implement this. I dont want to add abstract method in base class as it is extended by many classes

Answer 1

Your issue seems to be that the parent class BaseClass will be inherited by many children, but only a small subset of the children will need to implement letsGo . I think the easiest solution is to make an intermediate subclass, say MediumClass (extending BaseClass ) that contains the method letsGo and then make Abc and Xyz inherit that. Finally, make the run method take the intermediate class as the argument.