XOM API for Processing XML with Java

[jcowan AT reutershealth.com]

Elliotte Rusty Harold scripsit:

> 3. The Element copy constructor, and by extension Element's copy 
> method. This is the one I'm on the fence about. It's not that much 
> harder to make it non-recursive. The problem is that if I do so, then 
> descendant elements can lose their subclasses since the copies will 
> be created with the Element constructor and copy() method rather than 
> the Element subclass copy constructor and copy method. This could be 
> fixed but only by adding an additional protected method to the 
> Element API that creates an empty element of the right subclass which 
> copy could then call. 

Unfortunately, I think this is the important one, because it's not
replaceable.  If you foresee a problem with serializing, you can use a
different serializer, but Element.copy and Element(anElement) are critical
parts of the API.  And if you are running a server that is meant to handle
arbitrary incoming documents (and assuming you have some check for gross
size), then blowing up on nesting depth is really not acceptable.

A way to avoid the API wart would be to check if the element to be copied
is an actual Element or a subclass, and in the latter case, using
sourceElement.getClass().newInstance() to call the argless constructor.

-- 
Do NOT stray from the path!             John Cowan <jcowan AT reutershealth.com>
        --Gandalf                       http://www.ccil.org/~cowan