RE: Getting the JAXP reference implementation to work with Xalan. ..

[Brian Young <Br...@sas.com>]

Hello Scott,

Sorry for the belated reply, I was under the weather.

That would be great.  I'll also take a look at the task, but I suspect that you or Gary could knock it out better than I can.

Thanks,
   Brian Young


-----Original Message-----
From: Scott Boag/CAM/Lotus [mailto:Scott_Boag@lotus.com]
Sent: Monday, July 31, 2000 6:18 PM
To: xalan-dev@xml.apache.org
Subject: RE: Getting the JAXP reference implementation to work with
Xalan. ..



> As for a liaison class for JAXP, it would be wonderful if it existed.

I really don't think this is a big deal, and could probably be built into
the default liaison.  When I work on Norm's code later this week, I will
try and address this, if someone doesn't beat me to it.

-scott




                                                                                                                   
                    Brian Young                                                                                    
                    <Brian.Young@        To:     "'xalan-dev@xml.apache.org'" <xa...@xml.apache.org>           
                    sas.com>             cc:     (bcc: Scott Boag/CAM/Lotus)                                       
                                         Subject:     RE: Getting the JAXP reference implementation to work with   
                    07/31/2000           Xalan. ..                                                                 
                    05:34 PM                                                                                       
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Hello,

Sean's option 4 read an awful like my option 2 to me too.

I'll try taking a stab at your first suggestion, converting the XML
persistence/restoration code to use launch Xerces instead of JAXP reference
implementation.

As for a liaison class for JAXP, it would be wonderful if it existed.  It
is a little premature to act on due to me, though, as I should do some more
research about having the JAXP reference code changed to Xerces first.  I
have *no* experience in DOM or working with XML parsers, so the task would
probably be beyond me.  I'll take a look at the source code, though, and
see if I can figure it out.

Since JAXP reference implementation supports DOM L1 and Xerces supports DOM
L1 and L2, I thought that it should "just work".  The documentation for
XMLParserLiaison says that that interface is needed "...to cover for
deficiencies in the DOM.".  What sort of deficiencies?  I'm clueless when
it comes to DOM (so far, I've just been focusing on writing XSLT and
blindly calling Xalan (and, by default, Xerces), but I can take a stab at
fixing any deficiencies that the XML persistence/restoration code may have
in it.

Thanks,
   Brian Young


-----Original Message-----
From: Gary L Peskin [mailto:garyp@firstech.com]
Sent: Monday, July 31, 2000 3:21 PM
To: xalan-dev@xml.apache.org
Subject: Re: Getting the JAXP reference implementation to work with
Xalan...


Brian --

It seems like Sean's option 4 is the same as your option 2.  There
shouldn't be any problem switching from JAXP to Xerces since Xerces
should implement all of the same methods as JAXP.  You might just give
it a quick try.  Switching the .jar files and maybe fixing up the
original instantiation of the parser should be all that is required.

It would be nice if someone did create a liaison class for JAXP and
contributed it.  I'd do it myself except I don't use JAXP and I'm
focusing on studying the 2.0 extension mechanism with the hopes of
jazzing that up a bit.  Looking at the source for XercesLiaison class,
it doesn't seem like coding a JAXP liaison class should be too daunting
(says he who's not volunteering to do the work).  This source should
have been downloaded with your .zip file and is available online from
the CVS repository.

If a JAXP liaison is something you really need, let me know and give me
a ballpark timeframe (> yesterday).  I'll download JAXP and see about
converting my stuff to temporarily use it and create a liaison in the
meantime.  I'd like to see Xalan work with all of the XML parsers out
there.

Gary

"Timm, Sean" wrote:
>
> How about option #4: Since Xerces is already a JAXP implementation, just
use
> that.  :)
>
> - Sean T.
>
> -----Original Message-----
> From: Brian Young [mailto:Brian.Young@sas.com]
> Sent: Monday, July 31, 2000 12:26 PM
> To: 'xalan-dev@xml.apache.org'
> Subject: Getting the JAXP reference implementation to work with Xalan...
>
> Hello,
>
> I am working on an application that persists its data as XML.  Code is
> already in place using Sun's JAXP reference implementation of an XML
parser
> to persist and restore this XML.  I am tasked with writing XSLT to
transform
> this XML into a JSP.  I chose to use Xalan as my XSL processor, as Sun
> doesn't have one ready in the time-frame that I need to finish my work.
> I've gotten the transformation of the XML to JSP working, but only from a
> separate VM.  It is, at this time, using the default Xerces XML parser.
>
> When I try to get the JAXP reference implementation jars (jaxp.jar and
> parser.jar) and the Xalan/Xerces jars (notably xerces.jar) to co-exist in
> the VM (my application running) I end up with the XML persistence code
that
> should use the JAXP reference implementation trying to use Xerces
instead.
> I imagine there are conflicts from trying to have all the jars in the
same
> VM.
>
> I'm mulling over my options, and would like your input.
>
> 1)  Make JAXP reference implementation and Xerces exist together
peacefully
> and each only be used when appropriate (JAXP reference for the XML
> persistence/restoration, Xerces for the transformation to JSP).  Is this
> possible?
>
> 2)  Convert the XML persistence/restoration over to use Xerces.  Right
now,
> the tree that is parsed is a DOM Level 1 tree, not the DOM Level 2 that
> Xerces likes.  Is that an issue, or will Xerces handle down-level DOM
Levels
> greacefully?  Also there is a significant bit of resistance to do this,
as
> this existing code is stable and working to specification.
>
> 3)  Make the XML to JSP code use the JAXP reference implementation rather
> than Xerces.  It is my understanding that I need to provide a liaison
> implementation in order to accomplish this.  Does a liaison to the JAXP
> reference implementation exist yet?  How daunting is such a task?
Lastly,
> where can one find documentation on the class and interface that must be
> implemented?  The JavaDoc of those is not enough for me to go by, I'm
> afraid.
>
> Any thoughts are greatly appreciated.  I'm trying to use Xalan v1.1.D01,
by
> the way.
>
> Thanks,
>    Brian Young