XOM API for Processing XML with Java

[Elliotte Rusty Harold <elharo AT metalab.unc.edu>]

At 9:59 AM -0800 2/11/04, Nils_Kilden-Pedersen AT Countrywide.Com wrote:
> Now you've got me confused. LeafNode saves code duplication AND fits your
> abstraction perfectly.
> The semantics make sense, so why delete it? To save a class?

I'd like to save the class certainly. The fewer public classes the better.

I can't see where someone is really going to use LeafNode as such given that:

1. Not all children of ParentNodes are LeafNodes
2. Not all LeafNodes are legal children of an element

At one point, LeafNode did have a little more meaning but over time 
it's been whittled down to just two very simple methods. It makes the 
inheritance hierarchy a little deeper and less clear than it should 
be.

As far as saving code duplication, the two methods it keeps are 
one-liners. One always returns 0 and the other always throws an 
exception. If I really want to avoid that duplication I could make it 
a package-protected class which is called by delegation rather than 
inheritance.
--

  Elliotte Rusty Harold
  elharo AT metalab.unc.edu
  Effective XML (Addison-Wesley, 2003)
  http://www.cafeconleche.org/books/effectivexml
  http://www.amazon.com/exec/obidos/ISBN%3D0321150406/ref%3Dnosim/cafeaulaitA