XOM API for Processing XML with Java

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

At 9:37 AM -0600 3/12/04, Bradley S. Huffman wrote:

> If I subclass Element and override checkInsertChild to check that elements
> with local name "foo" can only contain children with local name "bar", what
> do I do about setLocalName? Think about the case of replacing nodes in a
> document.  Obviously I can create a "foo" element by recycling a existing
> element and using setLocalName, skipping the checks in checkInsertChild
> completely.

That's a good one! Devious thinking. I like it. :-)

You're right. That would be a problem with the current checkFoo 
startegy. However, I think the proposed strategy (make all mutator 
methods non-final) would plus the hole since the subclass that wishes 
to enforce the rules could override insertChild and setLocalName. 
Because the constraints would have to be verified across several 
classes, to really enforce it, a parent would have to never allow an 
object from outside its known friends to be added to itself, but I 
think that would be possible.
--

  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