RE: building an object model of a XML schema

["Bullard, Claude L (Len)" <clbullar@ingr.com>]

Thanks Ron. Makes sense.  

What if the idea is that the XML Schema is a set of reusable 
types, a toolkit that is then included/imported/redefined/substituted 
into other application languages?  I also haven't 
exported a schema out of UML, but it seems to me it 
may include classes that such a design would not use.

This probably turns on what you said:  if one is 
designing objects, design objects.  OTOH, there 
is that intermediate step where one is not quite 
designing documents in the print document or online 
document sense, one is designing reusable data 
sets more like relational tables than objects 
(no explicit operations) and a little less like 
a document (no explicit assembly).

Len 
http://www.mp3.com/LenBullard

Ekam sat.h, Vipraah bahudhaa vadanti.
Daamyata. Datta. Dayadhvam.h


-----Original Message-----
From: Ronald Bourret [mailto:rpbourret@rpbourret.com]

"Bullard, Claude L (Len)" wrote:
> 
> An excellent paper, BTW.
> 
> In it, you suggest that it is better NOT to
> generate classes from XML Schemas.  It is better use
> a data modeling language such as UML and generate the
> schema from that.  Do you still support that position?

Yes, although it's based on theoretical work, not real-world experience.

XML Schemas are designed to model XML documents, not objects.
Consequently, you get some weirdnesses when trying to map the schema
data model to an object model. If your application really thinks in
terms of objects, better to start with an object/generic modelling
language and go the other direction. That way, the XML schema is just a
serialization syntax, not a model.