Ok, here's my problem...
i've built a tree and now i'm walking down the tree and trying to extract values from the objects as i walk down it.
But my problem is that the method i call depends on the type of the object. I would have to call intValue() if the object was of type Constant in my program b/c this type would contain an object Integer and i would charValue() if the type was Variable in my program b/c this would contain a Character. Both Constant and Variable have a parent class called ETree. How do I deterine what type of ETree i am looking at as I walk down the tree???