Failure to load installer-desc extension if server is redeployed

Question

Hello,
We have an application that is deployed using webstart using jre1.6.0_06 Everything works for a first time deployment to a client. However, if you stop the server, wipe it clean and then reload the same server configuration, the first time you attempt to run the application from the client it fails with
MissingFieldException[ The following required field is missing from the launch file: <application-desc> | <applet-desc>]
   at com.sun.javaws.Launcher.prepareLaunchFile(Unknown Source)
   at com.sun.javaws.Launcher.prepareToLaunch(Unknown Source)
   at com.sun.javaws.Launcher.launch(Unknown Source)
   at com.sun.javaws.Main.launchApp(Unknown Source)
   at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
   at com.sun.javaws.Main$1.run(Unknown Source)If you acknowledge the error the download fails. If you try to launch again no error is seen and everything works fine.
There seems to be some confusion on that first execution from a client that has some state in the cache. If you clear the client cache after redeploy of the server it also works without generating that first failure.
The above failure is seen while loading an extension. The client attempts to load a .jnlp file that makes reference to an extension of type <installer-desc> The extension is parsed correctly and all the jar and nativelib entries in the extension are seen and downloaded correctly ( I used the Fiddler proxy to watch the traffic between client and server). However we get the error about a missing <application-desc> tag - when processing this file, well ya, it isn't an application, it is an extension. Fiddler was able to parse the XML that was downloaded and there were no errors.
I tried to download the webstart client source but I could only get the 5.0 version. Looks like there were some extensive changes since the method names do not match up that well.
Any tips on how to debug this further?

Answer 1

This problem seems to be resolved if you run 1.6.0 Update 10 beta on the client.
It looks like extensive changes have been made to the way applets and webstart work in this update.