Does Axis support automatic marshalling of document-style messages? I was under the impression it does not, which was why I suggested a DataBindingProvider might be useful to add this support. I agree that document-style is a better approach for the future, though I'd hardly call it a "predominant consensus" at this point. AFAIK document style interfaces are not as widely supported as RPC style, though, and I'm surprised to see your statement that most SOAP implementations support automatic marshalling for document style. Can you give me any figures for this?
As for "no problem building automatic serializers" I have to disagree. A Schema definition does not, in general, provide enough information to directly map to Java data structures. If you use an approach where the data structures are either pre-generated from the Schema or constrained to obey a predefined mapping to and from the Schema you can get around this, but that's hardly automatic.
I'm also puzzled by your statement that it's difficult handle multi-referencing object structures using document style. Is there a reason this can't be handled with ID/IDREF or key/keyref links?
Thanks,
- Dennis
Dennis M. Sosnoski
Enterprise Java, XML, and Web Services Support
http://www.sosnoski.com
Anne Thomas Manes wrote:
Dennis,
This is a pretty antiquated view of document style. Document style is no
longer used just for XML messaging. Most SOAP implementations support
automatic marshalling of both RPC-style and document-style messages. As long
as you have a WSDL description of the message structure, there's no problem
building automatic serializers.
The predominant consensus in the industry at this point is to use
document-style by default. Document style is much easier to validate,
transform, and manipulate. The primary reason to consider using rpc/encoded
is if you need to send multi-referencing object structures. SOAP encoding
does a really nice job marshalling these structures. It's much harded to
represent them using literal XML Schema. But if you're not using multi-refs,
it's a better practice to use document-style.
Regards,
Anne
-----Original Message-----
From: Dennis Sosnoski [mailto:[EMAIL PROTECTED]]
Sent: Thursday, November 21, 2002 1:25 PM
To: [EMAIL PROTECTED]
Subject: Re: Document style web services
Hi Matt,
The whole point of document style is that your application gets passed
the XML message payload as XML document fragments. See the "message"
sample for an example of this. With a document style interface your
class would look like:
public class SomeXMLService {
public Element[] someXMLMethod(Element[] elems) {
...
}
}
If you want to convert the XML into objects you need to do it yourself,
perhaps using a framework such as Castor (http://www.castor.org). I know
there's been some integration of Castor with Axis, though I think this
was for custom serialization with RPC style.
This brings up an interesting point, though. Why not have a Java
DataBindingProvider as a replacement for the MsgProvider? This should
allow easy use of document style while converting seamlessly between XML
and objects without the application needing any special code. I'm
looking into some data binding code currently, perhaps I'll see if I can
work in this direction.
- Dennis
Dennis M. Sosnoski
Enterprise Java, XML, and Web Services Support
http://www.sosnoski.com
