On 5/7/06, Jirka Kosek <jirka@k...> wrote:

> My understanding of NVDL is that its main purpose is validation and
> JNVDL thus implements standard Java API for invoking validation. So when
> your document is valid, there is no return. If there are some errors (be
> it validation problem on NVDL level, or validation errors against
> particular schema referenced from NVDL) you get these errors (as
> exceptions, or you can register your own ErrorHandler to handle them on
> your own).
>
> Of course, JNVDL internally does sectioning of input XML document and
> then dispatches these sections (fragments) for validation against
> particular schemas (you can monitor this process by using -d option on
> command line interface). So it is possible to create some API which can
> be used to read fragments and their schemas (because JNVDL knows this),
> but it is not big priority (at least now) for us.
>
My understanding of NVDL is in agreement with yours. But I think most
developers would want the validation process to lead to an output of
the seperated xml, this could be used, for example, as the first step
in a pipeline so that:

NVDLValid -> handleValidSeperatedXML

NVDLInvalid -> handleNonValidSeperatedXML

otherwise I think, that for most applications likely to be
encountered, the NVDL validation is useless because after NVDL
validation they will have to (or want to [not the same thing, but most
people act as if it were]) do the same thing they would have to do
without NVDL validation, namely seperate out the namespaces.

And if they seperate out the namespaces correctly than it is not a big
thing to validate the seperated XML, if they seperate them incorrectly
(really, there are developers I would not trust to do this) well then
it would be nice if their validation took place after seperation.

At any rate if the developer has to seperate the namespaces themselves
I am sure they are going to want to validate the document after
seperation.

And if they are doing that, why not do just that and skip NVDL?

The use case for NVDL without some way to hook into the seperated
streams will seem very small to the average developer, I think.

This is not meant as a hit against NVDL, as I am quite a fan of it and
the DSDL work in general.

Cheers,
Bryan Rasmussen