Calling subclass/method in a parentclass

Question

class A extends Frame implements ActionListener
Button ok;
public void actionPerformed (ActionEvent ae)
try
if (ae.getActionCommand().equalsIgnoreCase("OK"))
/* HOW DO I CALL CLASS B OR METHOD IN CLASS B ONCLICK OK BUTTON*/
catch(Exception e)
System.out.println(e);
class B extends A
B()
//create a panel and will show some buttons, textfield etc.
public static void main(String args[])
new A();
}

Answer 1

Is it so hard to click on the Formatting Help link, that I provided earlier AND that is at the top of the screen where you post the question?
Is it so hard to ask your question OUTSIDE of the unformatted code, so as to make it easier to find?
That aside:
HOW DO I CALL CLASS B OR METHOD IN CLASS B ONCLICK OK BUTTON
You can't. What you CAN do is make your super class abstract, with an abstract method, make your subclass a concrete implementation:
public abstract class A extends Frame implements ActionListener
  protected Button ok;
  public void actionPerformed (ActionEvent ae)
    try
      if (ae.getActionCommand().equalsIgnoreCase("OK"))
        doOKCommand();
    catch(Exception e) /*Catch specific exeptions, much better than the general excpetion */
      e.prinbtStackTrace(); /* get much better info this way... */
  protected abstract void doOKCommand();
  public static void main(String[] args)
    A anA = new B(); //Note, use new B() to get B functionality!!!
} //end of class A
public class B extends A
  B()
    //create a panel and will show some buttons, textfield etc.
  protected doOKCommand()
    //Do real Stuff
}