Re: xmlwriter and xmlfilter

Nic Ferrier wrote:
> Luca Dall'Olio <[email protected]> writes:
> 
> 
>>I am on thesis on archiving *huge* quantities of xml-signed data.
>>Among other things I have to write a single xml file more than 4 Gb size
>>(1 dvd) so I decided to use Sax.
>>
>>Since the Xerces default content handler does not have a flush() method
>>(it keeps everything in memory until the endDocument() method call), I
>>changed to Dom4j XmlWriter and then I changed again to Gnu Jaxp
>>XmlWriter, because Dom4j does not produce canonalized output.
>>Now I would like to send the canonalized sax events to a digester in
>>order to produce the document hash and then prettyprint the sax events
>>into an outputstream (the final file).
>>
>>First question:
>>Do you think that I chose the right approach?
> 
> 
> Broadly, yes.
> 
>  
> 
>>Second one:
>>How can I send the XmlWriter events through an XmlFilter (I would prefer
>>not to use the Gnu Jaxp pipeline package: I would like to write
>>implementation independent code as far as possible), since XmlWriter
>>does not implement the XmlReader interface? Should I extend the
>>XmlWriter to do implement it?
> 
> 
> Why can't you filter the events before they get to the XmlWriter?
> using an ordinary SAX chain
> 
> 
> Nic
> 
> 
> 

I could not understand why XmlFilter has to be at the end of the event 
chain, now I do.
I cannot use an ordinary SAX chain because I need to produce both Pretty 
Printed and Canonicalized Xml at the same time, in order to write a nice 
.xml file and calculate an hash out of it. My actual solution (it 
works!) is to fire SAX events using a TeeConsumer and then serialize 
with a couple of TextConsumers. Thank you very much for your helpful 
suggestions!
Luca Dall'Olio