Regarding the portion of this thread having to do with xslt
implementation that doesn't require lots of memory....

Rather than subsetting XSLT, i think an interesting approach would
be a lookback window, sized in bytes or nodes or sax events.

Lets assume that the stylesheet is read into any data structure you
like, just once.

Now a moby xml instance arrives, and starts spewing sax events at you.

You start applying the stylesheet as soon as your window fills up,
and generate a runtime error if you happen to get to an operation that
requires you to exceed your window.

A static analysis of a stylesheet could indicate language that *might*
require lookback or full-document-scan, but that is overly aggressive,
relative to just waiting to see if for a particular instance it is
actually necessary. 

-mda

--On Wednesday, November 03, 1999 10:00 AM +0000 Kay Michael <Michael.Kay@xxxxxxx> wrote:

>> If you want to process very large documents with a small JVM 
>> heap using XSLT, the alternatives I see are:
>> 
>> - drastic subsetting of XSLT
>> 
>> - use a RandomAccessFile to provide random access to the XML document
>> without having to keep it all in memory
>> 
>> - use a multi-pass strategy
>> 
> 
> Or the option provided in Saxon 4.7, which allows you to apply the
> stylesheet to a subtree of the source document as if it were an entire
> document: so for example you can apply your stylesheet to each chapter in
> turn, meaning you only need enough memory to hold one chapter. 
> 
> Mike Kay
> 
> 
>  XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list



 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list