Type of object?

Sup /prog/riders?

I have a common problem (I guess).
I have an abstract class "X" and two classes ("A" and "B") that inherit from it. Also I really need a list that can handle both of them.

List<X> mylist;
mylist.add(A);
mylist.add(B);

Now I need to pick out all items of type A and do something with them, possibly using methods only available in class A and NOT in X or B. In ENTERPRISE JAVA there is "instanceof" but using that sounds just as hacky as saving a type in every object.


Is there a CLEAN way of determining if the object from the X-list is of type A?
Not Java-specific, rather OOP in general.

I don't see how this changes anything.  In Java you still have no access to type-specific object methods or object variables unless you cast it into that object.  I can think of AWTEvent handling as an example.  After I determine if the object is of type Mouse*Event or type KeyEvent, I still have to cast it into one or the other to access the specific of its event report.