WLI : how to validate XML / MFL instances against specifications.

Question

Hi,
Does anybody know how a variable inside a workflow
containing XML or binary data can be validated against
an XSD or MFL?
Greetings,
Davy Toch

Answer 1

You can tell the parser where to look for external entities. The parser allows
you to set your entity resolver -->
Using JAXP --> documentBuilder.setEntityResolver(new MyEntityResolver());
Using Xerces DOMParser --> parser.setEntityResolver(new MyEntityResolver());
Your Entity Resolver implements: InputSource resolveEntity(String publicID, String
systemID). You can implement this method to find and return an InputSource loaded
with your xsd. So the parser will call this method -- and pass in the systemID
it is looking for. Based on that systemID, you can have the method look in the
appropriate location.
"Karthik V" <[email protected]> wrote:
Jared,
That is interesting... If you do not specify the location of the schema
in
your instance document, then how do you validate it. You said your app
will
lookup the schema location. Does this mean that you do 2 step parsing?
First you parse the document and get the schema name (Say MySchema.xsd),
next you identify the schema location and parse it once more for validation
against the schema.
I know it is slightly off topic. But I would be interesed in understanding
your idea.
Thanks.
/k
"Jared" <[email protected]> wrote in message
news:[email protected]...
I think you could attack this a few ways.
If you pass the XML to your BO, you could override your parser's entityresolver
-- and redirect the xsd lookup to the actual location of XSDs. I knowthat you
said you are keeping them in the WLI repository -- but do you loadthem
into the
WLI repository from the filesystem or something? That filesystem couldbe
where
you look for the xsd.
Also, you MIGHT be able to use the XML Registry -- which also can beused
to redirect
where your BO looks for the XSD.
When I reference my XSD or DTD, I make sure that it does not containa
protocol
(eg http://). We made a rule that we will all use the filename of
the
schema
(eg asdf.xsd). Then each app could look where they wanted for theschema.
I
know this introduces problems of version control -- but we didn't wantto
have
a single point of failure for all applications just because the DTDserver
may
be down.
"Davy Toch" <[email protected]> wrote:
Hi,
I also thought of using a Business Operation, but the problem is how
to
reference the
specification in the xml instance when the specification is located
in
the
WLI repository.
I thought of recuperating the needed specification in a String variable
and
passing that too
to the Business Operation. But this poses a problem forSAXParser/DOMParser,
since
you can't specify that the specification is actually available ina
String.
Regards,
Davy Toch
"Jared" <[email protected]> wrote in message
news:[email protected]...
I don't know about MFL, but you can validate an XML against an XSDby
calling a
java class (business operation) and letting that java class validate.
I know this probably insn't the most efficient way -- or the mostappropriate
way to do it -- but it should work.
"Davy Toch" <[email protected]> wrote:
Hi,
Does anybody know how a variable inside a workflow
containing XML or binary data can be validated against
an XSD or MFL?
Greetings,
Davy Toch