Question

Hi I am facing a design problem which I think it should be quite common:

public abstract class Parent
{
    ...

   public boolean itsOk()
   {
       return true;
   }
   public void execute()      
   { 
       if (itsOk()){
          System.out.println("done");
       }
   }
}

I need to be able to override itsOK() function in any subclass inherited from ‘Parent’ even if arguments are different.

public class Example extends Parent
{
    public boolean itsOK(int a)
    {
       if (a==1)      return true;
       else           return false;
    }

}

Then when I call execute, I want the subclass’ itsOk() method to be invoked.

public static void main(String[] args) {
    Example e=new Example();
    e.execute();
}

This works ok if the subclass’ itsOk() method has no arguments (like the ‘Parent’s method), so it’s an overriding case, but how can I make it when arguments are different?

Answer 1

In such a case I would rather try to have the same method signature in the parent and the child class, ie. a real overwriting and not an overloading. Then, your parameter a could be a member of the class Example which would avoid the need for a parameter. Of course it strongly depends on the rest of the code.