W3C home > Mailing lists > Public > www-ws@w3.org > July 2005

RE: XML Schema patterns for databinding

From: <paul.downey@bt.com>
Date: Fri, 29 Jul 2005 09:20:27 +0100
Message-ID: <2B7789AAED12954AAD214AEAC13ACCEF2709E523@i2km02-ukbr.domain1.systemhost.net>
To: <Mark.Hapner@Sun.COM>, <www-ws@w3.org>

Mark

I think your rant does express a strong view that the publisher of a 
Schema should be minded on the data and form of the documents
to be exchanged. I agree wholeheartedly.

The difficulty is how to approach this task without alienating the large 
number of customers who expect to be able to use WSDL2code generators 
and XML databinding tools such as JAXB. We tried to highlight this issue
in BT's paper for the recent W3C Workshop on XML Schema 1.0 User 
Experiences:
http://www.w3.org/2005/05/25-schema/BT.html

We see great value in publishing patterns of XML Schema which are
known to work well with databinding tools. There is nothing to stop 
the author of a business document from using aspects of Schema
outside of these patterns, but at least they, and a consumer of 
their schemas would be aware that they were unlikely to work well
with code gen and databinding toolkits. 

I also see little harm in publishing patterns which express how
to represent vectors, maps and other data constructs in general, so 
long as they are not programming language and the resulting patterns 
are vanilla XML Schema and XML documents.

As you say, XML decouples implementation from the data being 
exchanged. So what does it matter if i send a repeated list of elements 
and describe it in a way that becomes a vector in a databinding tool
but remains open to being manipulated in XSLT, DOM, etc?

Paul 


-----Original Message-----
From:	www-ws-request@w3.org on behalf of Mark Hapner
Sent:	Tue 7/26/2005 3:10 AM
To:	www-ws@w3.org
Cc:	
Subject:	RE: XML Schema patterns for databinding


A small rant ...

While some uses of XML will be to marshal program data structures  
between applications, in the business world this is not the issue.  
The issue is to capture the structure and semantics of business data  
such that these can be communicated unambiguously. This is the  
objective of UBL, HL7, etc.

Possibly I'm missing something but I don't see what this has to do  
with transmitting a collection from one program to another. I thought  
the objective of web services was to decouple program data structure  
implementation from service document schema.

It might be more useful for this WG to study how XML Schema could  
more simply and directly capture the business document design being  
done by the various vertical market orgs that are trying to apply it.  
I hope these org's are not thinking in terms of 'collections,  
vectors,  maps and graphs' as their design primitives.

-- Mark
Received on Friday, 29 July 2005 08:20:34 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 3 July 2007 12:25:49 GMT