W3C home > Mailing lists > Public > semantic-web@w3.org > March 2005

RE: Style question

From: Kirkham, Pete (UK) <pete.kirkham@baesystems.com>
Date: Wed, 09 Mar 2005 09:53:58 +0000
To: ben syverson <w3@likn.org>, semantic-web@w3.org
Message-id: <820DBA1A8ECA1D45A557AFD03CF4DEE06E5067@glkms0015>


> Wow. You must be one of those binary XML people too. :)

In as much as using binary for resource limited devices, yes, ASN.1 is still better than anything I've seen for that - it's an established standard with a history of use in industry; in terms of the web in general, no, the merit of supporting a 'text' layer of on top of the underlying binary character encoding easily outweigh the cost.

>I totally disagree that RDF/XML is unreadable, and think that this attitude is
toxic to the web.

Fair enough. I think it is, and could at the very least be revisited to make it better; I very much doubt anyone who isn't very interested in the technology (rather than the application) will choose to read it.

>I don't think I could disagree more. How do you expect anyone to become
an expert in RDF/XML if it's made totally opaque by its users?

OK, then I'll rephrase it as 'don't expect anyone who isn't an expert (or wants to become an expert) in RDF/XML to view your sources'. Most _users_ of the web don't view source. I would not say that the XMI encoding makes the RDF more opaque than the RDF/XML encoding does; what it does do is enforce a seperation of uuid (which may also be a uri) and the href for more information - there is no means of confusion of identity and location. It's also not as readale as HTML, but then it's encoding a more complicated model.

> Isn't the whole point of RDF to move away from such custom languages?

Using an XMI encoding for RDF is no more a 'custom language' than using the RDF/XML encoding- they both map your custom metamodel (Person, Car, Currency etc) to XML in a standard way. The sample provided is as much RDF as yours - the same RDF in fact; it just uses the software industry's standard mapping of that metamodel to XML, rather than the W3C one. In particular it uses version 2.1 of that standard because the first version was considered too unreadable that they *changed it* rather than saying 'you have to become an XMI 1 expert to read this'. If a version 2 of RDF/XML came with a requirement for human usability, then that may be as or more suitable, but I can't see there being any real gain over using the existing XMI standard, other than the political one of having everything under W3C control.

>"View source" on this might help someone understand XML, but besides XML syntax, it won't teach them anything they can re-use.
Apart from being able to read and manipulate instance data from any UML 2 or CWM (Common Warehouse Metamodel, the industry standard data warehouse interchange mechasism) tool that is, or about RDF (the abstract model) as it's RDF data. Where are the RDF/XML tools being used in industry?

>Besides, not all browsers support XSLT, and there's no way I'm spending my server resources shuffling XML from a good format into a useless one.

So it's OK to send the raw RDF/XML encoding to the browser but not the raw RDF-XMI? Keep the XMI format data (or your own internal format- there's no requirement that an XMI tool has XMI other than at its perimeter) and use a style sheet _when someone requests the RDF/XML format_ for the data. What gets sent to the browser isn't normally RDF (in any encoding), but something suitable for browsers (unless you're doing something with a custom, RDF/XML aware browser, as so are targetting only people who are interested in RDF/XML so most of the comments don't apply - your users will make the effort to learn to read it, they will want RDF/XML, they won't care about integration with existing toolsets, etc.etc.).

And try and think about the relative take up of UML vs RDF before you label the UML/CWM interchange format as 'useless'.


Pete

********************************************************************
This email and any attachments are confidential to the intended
recipient and may also be privileged. If you are not the intended
recipient please delete it from your system and notify the sender.
You should not copy it or use it for any purpose nor disclose or
distribute its contents to any other person.
********************************************************************
Received on Wednesday, 9 March 2005 09:54:12 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 1 March 2016 07:41:45 UTC