OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.


Help: OASIS Mailing Lists Help | MarkMail Help



   RE: [xml-dev] Entity resolution vs. URI resolution

[ Lists Home | Date Index | Thread Index ]

> From: Edwin Goei [mailto:edwingo@sun.com]


> > Basically, my take was that the parser should throw an event when it
> > encounters content that it cannot find an existing schema 
> resource to
> > handle.  The handler should have access to any previously 
> encountered
> > xsi:schemaLocation, the namespace URI and local name of the 
> content that
> > caused the event and the untyped content of the start tag 
> (so that you could
> > use something like an version attribute).
> Perhaps, there are plans to implement a more general scheme in the
> future.
> -Edwin

I hope so. The model Curt Arnold describes makes a great deal of sense. I've
said that before on this list, and I'm surprised more people haven't raised
this as an issue.

The model of relying exclusively upon the schemaLocation attribute is
utterly useless to me. I'm really surprised that the Xerces team has still
not provided an alternative mechanism that the application can control. (I
think I recall that they added an XMLReader property, at one point, that is
the equivalent of the schemaLocation attribute. That still sucks.) I hope
that is just because they have not gotten to it, yet, rather than reflecting
that they fail to see the value in such an approach.

The callback mechanism makes far more sense to me. Microsoft's XML SDK lets
you construct a schema cache and associate schemas with namespaces in
advance of parsing. I would have preferred that they let me provide a
callback, so I don't have to load the cache in advance with every schema I
might use. But what they have provided is still far better than what Xerces

I love Sun's MSV. That's a nice library. I haven't tried implementing
something with it, yet, that can handle mixed namespaces in a document,
though. Looking at the APIs it looks like it will a fair amount of effort to
do, but it looks doable. If it wasn't for MSV giving me an alternative I can
pursue, I'd be really frustrated over the way Xerces does things. I also
like the fact that MSV lets me work with other schema languages.


News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS