User defined Exception in Stateless Java Class WS

Question

Hi,
I'm experimenting with publishing some of my application's Java classes as web services under OC4J 10.1.2. I've been quite successfull to do so, but I'm stuck into a problem trying to have my class's methods throw my own type of exception and retrieving it at the client side.
I'm using the proxies downloaded from the web service's automatic HTML page, and I see in the source code version that the proxy class specifically throws a org.apache.soap.SOAPException whenever there's a fault in the response message.
What I've done is simply to create a type derived from Exception with a String (message) and an Integer (code) properties, with just my own constructor that accepts two parameters corresponding to that properties. Then I make the methods in my Java class throw that exception.
I've tried both using both an Interface and a class, and also using just a class as parameters to StatelessWebServiceServlet / Web Service Assembler.
I can't find anywhere in any docs that explains how this can be done in OC4J. I believe that throwing user-defined exceptions is included in J2EE 1.4 and so I think that there should be a way to do it in OC4J if it is compliant. Maybe there's no way, but I couldn't find any reference to that neither.
I'll greatly appreciate any light on this issue.
Thanks in advance
Juan Alvarez Ferrando
Mensaje editado por:
user517323

Answer 1

Thank you for your answer.
I'd like to know something more about how far does that limited support go, in case it could be of some use.
On the other hand, and just for the sake of constructive discussion, though I've contemplated the option of encoding error conditions on the result type, I always found that to be an ugly style from a interface design standpoint (not ws specifically but in general system desing terms), and when I saw a standard way to communicate custom error information separated from normal response I thought it to be the right way to go. After all, exceptions are just the way Java implements this design principle that has also found a place in most currently successful software environments (PL/SQL, .Net, ...).
I don't expect to extend the meaning and programmatic use of Java exceptions to my ws clients, but to be able to communicate detailed error condition information as the standards contemplate (faults), which as I understand from your kind answer is out of my reach in 10.1.2.
I have no experience with other ws platforms but I'd like to believe that if wsdl:fault is in the standards, those claming compliance will support it to the extent necessary to make it usable and interoperable as it is the way the standard covers error communication (and so that's why it is included in 10.1.3). I also beleve this would bring better interoperability than our home-made result types including error information, that no other application without our custom specifications can understand.
Also better interoperability would come from that than for example what I now see in 10.1.2, where all exceptions are communicated to the client with a faultcode of soap:Server, which I believe to have the standard meaning that there's a chance for the client to success retrying later without modifying it's request. This translation could be better suited for Java errors (unrecoverable) but not for all kinds of exceptions, and so in this question, custom exception support could also improve interoperability with systems that interpret SOAP fault codes.
Thank you.
Juan Alvarez Ferrando