W3C home > Mailing lists > Public > xml-dist-app@w3.org > February 2002

Re: Reflective systems

From: Marwan Sabbouh <ms@mitre.org>
Date: Tue, 5 Feb 2002 08:20:13 -0500
Message-ID: <024a01c1ae47$d8658f10$253e5381@mitrezf21xy5nj>
To: "Kurt Cagle" <kurt@kurtcagle.net>, <xml-dist-app@w3.org>
In my previuos research on middleware, I found that strong typing is a
necessary condition for reflective systems.  Strong typing means that the
inheritance tree is sent with every method invocation.  In this way, RDF may
have much value to add beyond just interfaces.  Actually, RDF is at the
heart of everything I am doing at the moment, and it is proving extremely
useful.  ( I am hoping to get a paper out soon on RDF)

Marwan

----- Original Message -----
From: "Kurt Cagle" <kurt@kurtcagle.net>
To: <xml-dist-app@w3.org>
Sent: Tuesday, February 05, 2002 2:14 AM
Subject: Re: Reflective systems


> I'm jumping into this in the middle, so may be missing something, but I
> would concur with the assessment that one primary disadvantage that binary
> RPC mechanisms have is their inate inability to be self-descriptive. The
> IDispatch mechanism works effectively if you have an IDL, but if you don't
> then you're basically stuck in the dark about the characteristics of an
> object (especially, as with many scripting interfaces, the core object
only
> acts as a proxy mechanism). The power of XML is not only that you can have
a
> descriptive interface, but you can in fact have any number of them - XSD,
> RDF, WSDL, XTM, depending upon your requirements, and you can also utilize
> multiple interface descriptors simultaneously.
>
> ----- Original Message -----
> From: "Mark Baker" <distobj@acm.org>
> To: "Rich Salz" <rsalz@zolera.com>
> Cc: "Williams Stuart" <skw@hplb.hpl.hp.com>; <xml-dist-app@w3.org>
> Sent: Monday, February 04, 2002 3:06 PM
> Subject: Reflective systems
>
>
> > >
> > > > Absolutely true.  The wonderful thing about the Web is that this is
> done
> > > > *with* the Web.  It can describe itself.  RPC cannot.
> > >
> > > I disagree. Adding RDF to the web and saying it's reflexive seems no
> > > different from adding DII to Corba, IDispatch to COM, etc.
> >
> > I don't know about IDispatch, but IIRC, DII did not reify interfaces as
> > first class objects (i.e. they didn't get OIDs).
> >
> > Also, while that's necessary, it's not sufficient.  What's also needed
> > is a uniform means of resolving an identifer.  Neither CORBA nor COM
> > has that, but the Web has GET.
> >
> > MB
> > --
> > Mark Baker, Chief Science Officer, Planetfred, Inc.
> > Ottawa, Ontario, CANADA.      mbaker@planetfred.com
> > http://www.markbaker.ca   http://www.planetfred.com
> >
> >
>
>
Received on Tuesday, 5 February 2002 08:28:43 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:59:06 GMT