T320 Ebusiness Technologies Blog » Block 3: SOA, WSDL, SOAP, REST and UDDI

I finished the TMA (hooray) but not without some Herculean effort and wasted time spent wrestling with technical problems with Eclipse. So here are the problems and answers I found – may it save someone else some much needed time as the deadline approaches!

1) Minor hiccup – when I pasted the code directly from the PDF file, it had a syntax error caused by incorrect text formatting, so I used a text editor to break the lines properly.

2) When I used Eclipse to create the local web service and client, it could not find the class, so I tried again, using ‘Browse’ to find the Java class and select it that way. An option to test using Web Services Explorer appeared, but caused repeated ‘Windows – No Disk’ error in a dialog box. I eventually managed to close it and clicked Finish instead of Next. The client was not generated, but when I tried again it worked.

3) When testing for WS-I conformance with soapUI, the process caused some error messages until I created a directory for logs, but after that it worked.

4) The Axis Service Archiver could not find the class I was archiving. I tried again but then the archiver window was completely blank, with no options or input fields. The error console listed Java errors. I checked the Java configuration, and reinstalled everything, but Axis was not working. Technical support in the forums suggested my Java or Eclipse installations were corrupted, so I had to start from scratch in this case.
I deleted all my project files and reinstalled Eclipse again, created the service again and used the Axis Archiver to create an archive.

5) When using the WSDL on the OU server to generate a client for testing the service, I encountered more Java errors and an error relating to WAR archives. Eclipse could not generate client, and produced the error message: Could not publish server configuration: C:\T320\workspaceBlock3\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\conf\server.xml (The requested operation cannot be performed on a file with a user-mapped section open).
Thanks to technical support from the forums, I was able to get the test client working by setting up a new workspace for it, as some of the required files had been locked.

6) After publishing my UDDI business entry, I got an XML error when accessing the business discovery URL in the browser, which began: XML Parsing Error: xml declaration not at start of external entity. This error turned out either to be specific to Firefox, or at least not to occur in Internet Explorer. It wasn’t caused by anything I did, and wasn’t relevant to completing the assignment, so in this case I ignored it.

WSDL: Like memorising the phone book

admin — Sat, 02 Aug 2008 13:12:48 +0000

What with XML, SOAP and WSDL documents all using XML and XML Schema, they seem so alike. Starting to learn them by reading about them is like trying to memorise the phone book: I really need to get on with the practical activities to make some more sense of this. Thankfully (I think) there are many of these, but there isn’t much time for the TMA! I hope the reason WSDL is confusing is because it’s the first of the set that I’m reading about. The WSDL unit summary reminds me ‘WSDL is the language for describing web services so that they can be accessed and used by clients, either manually or automatically’… Hold that thought!

Made my first web service!

admin — Fri, 01 Aug 2008 12:37:29 +0000

I followed the instructions from the first activity in Block 3, clicked Finish to generate my web service in Eclipse, waited, waited, and got… a 404 Not Found page – aaargh! Had to go out almost immediately, but checked again when I got back and noticed port numbers being mentioned. So I tried switching off the Windows firewall, and hooray! My first web service!! It asked me my name and said Hello to me. (Ok so that part was not a surprise, but it was so great to see it working!)

On checking it out, I noticed all kinds of other files had been generated: WSDL, metadata, Java classes and libraries, and more – I guess that’s the rest of Block 3 then…