RE: Performance differences of Schema vs. DTD validation (qu

[Ryan O'Leary <Ry...@alltel.com>]

Jeff,

Thanks for the reply.  Your answer definitely makes sense; I wasn't sure if the
results were negligible or not.  I'll run a test with the NewTestament.xml file
(hopefully I can find a schema for it) to see the time differences of Schema vs
DTD.

I'm interested in implementing some sort of DTD caching, but I'm so new to the
Xerces code base I have alot of overhead and catching up to do.  Are there any
FAQS or documents out there besides the javadocs that can assist in learning the
architecture?  I plan on just running the parser in my IDE in debug mode and
stepping through each line of code as I parse something.

Thanks again for the reply,
Ryan

-----Original Message-----
From: xerces-j-dev@xml.apache.org 
Sent: Monday, February 05, 2001 11:45 AM
To: xerces-j-dev@xml.apache.org
Subject: Re: Performance differences of Schema vs. DTD validation (qu


Hi Ryan,

I don't know if this seem obvious but Schema validation is more complex than
DTD validation.
DTD validation does not check for content type validation for once,
therefore you would expect that Schema validation is slower than DTD
validation. That is the case.

So there is no performance gains in using a Schema for validation over a
DTD, unless you need to do content type validation, in which case the
programmer has to add the code to validate the content.

There are future specification or requests for the parser which is to be
able to cache Grammars ( DTD, Schema or any other Grammar available in the
future). I am not aware that anybody is already working on it but there is
an existing infrastructure in Xerces2 ( and to some extense in Xerces1) that
would allow this. It is just a matter of coding it ;>.

Thanks for your input,

            Jeffrey Rodriguez
            IBM Silicon Valley
            PIM application development





>From: "Ryan O'Leary" <Ry...@alltel.com>
>Reply-To: xerces-j-dev@xml.apache.org
>To: "xerces-j-dev@xml.apache.org" <xe...@xml.apache.org>
>Subject: Performance differences of Schema vs. DTD validation (que...
>Date: Mon, 05 Feb 2001 10:33 -0600
>
>Subject: Performance differences of Schema vs. DTD validation (question)
>
>Hi all,
>
>Are there any performance gains in using a Schema for validation over a DTD
>with
>Xerces?  Is Xerces currently faster using one over the other?
>
>Also, does anybody have any advice/tips for writing some sort of DTD
>caching
>mechanism into Xerces?  This would be an immense benefit to the parser,
>IMO.  My
>apologies if these questions have been asked/answered before on this list.
>I'm
>new to the community but plan on getting involved!
>
>Thanks in advance,
>Ryan
>
>---------------------------------------------------------------------
>To unsubscribe, e-mail: xerces-j-dev-unsubscribe@xml.apache.org
>For additional commands, e-mail: xerces-j-dev-help@xml.apache.org
>

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com


---------------------------------------------------------------------
To unsubscribe, e-mail: xerces-j-dev-unsubscribe@xml.apache.org
For additional commands, e-mail: xerces-j-dev-help@xml.apache.org