Re: SAX-ext Attribute + Entity Parsing

[Eric van der Vlist <vdv@dyomedea.com>]

Justin Couch wrote:
> 
> Eric van der Vlist wrote:
> 
> > Instead of adding methods to the SAX2 classes, have you considered using
> > the existing ones to pass additional elements/attributes from a specific
> > namespace to the applications using the existing ones ?
> 
> [snip]
> 
> > The applications would then see this as an element:
> >
> > <xxx:attributeDecl name="..." type="..." defValue="..." value="..."/>
> 
> My problem here is that I have no control over the DTD spec. It would be
> nice if I could do that, but it is far from my hands. I'm just paid to
> implement the code :)

You don't have to control the DTD, these elements will probably never
been materialized as XML text.

These elements are just added by the parser and could be filtered for
the "final" application when required.

[snip]

> Could you explain a little more what you mean by the layer modification
> bit? Apart from supplying my own custom *Handler implementations, as per
> the SAX2 spec, I'm not currently getting any lower into a specific SAX
> parser implementation.

I am probably very "XSLT biased"...

What I meant is that if you want to pass the info to applications that
are a layer above the SAX parser (for instance a XSLT transformation or
a DOM based application), this is much easier if you add elements using
the standard SAX API than if you add new methods.

On the other hand, those application that would need to handle this
information just above the SAX layer can filter these elements just like
they would do with your solution.

It's like using an existing channel to convey new information versus
creating another channel...

Between two adjacent layers, adding a new channel is not a big deal, but
if you need to traverse several layers, using an existing channel will
avoid the pain to modify them.

Using SAX events, the additional effort to filter those events that are
carrying attribute declaration is very limited (especially if you define
your own namespace for these elements).

Eric
> --
> Justin Couch                                    Author, Java Hacker
> http://www.vlc.com.au/~justin/               Java 3D FAQ Maintainer
> http://www.j3d.org/              J3D.org The Java 3D Community Site
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-- 
See you in Austin (Knowledge Technologies 2001)
              http://www.gca.org/attend/2001_conferences/kt_2001/mon.htm
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Eric van der Vlist       Dyomedea                    http://dyomedea.com
http://xmlfr.org         http://4xt.org              http://ducotede.com
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