Re: UnsatisfiedLinkError using Java Webstart with custom classloader

From:

Andrew Thompson <andrewthommo@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Mon, 17 Mar 2008 04:27:44 -0700 (PDT)

Message-ID:

<17c68ad5-d570-4f8b-bb78-db9b8636b04b@d4g2000prg.googlegroups.com>

On Mar 17, 9:42 pm, Andi <andreas.schnei...@skillworks.de> wrote:
...

I have a big problem to get my Application running on java webstart. I
have a custom classloader which will be used for some classes.

JWS *has* been known to be finicky with classloaders,
a lot of apps. used code that could 'discover' the
exact location to which it was downloaded. Changes
between 1.5 and 6.0 made that code break.

I am curious though to know exactly - *why*
are you using a custom classloader?

..Also I
need to load a dll which will be used by a native interface.

More on that below. *

(big snip...)

That works perfect when I have a normal client application but it
doesn't when I use Java Webstart.

Here my jnlp:

<?xml version="1.0" encoding="utf-8"?>

This is a fib, by the way. This is not
the SwingSet2 application. If we are going
to include comments, it seems sensible to
make them factual. ( And yes, I've been
caught out by the same thing myself ;)

<jnlp
  spec="1.0+"
  codebase="http://localhost/jws6-bugreport"
  href="Webstart6Bugreport.jnlp">
  <information>
    <title>Webstart 6 Bugreport</title>
    <vendor>Skillworks AG</vendor>
    <description>None</description>
    <description kind="short">None</description>
    <offline-allowed/>
  </information>
  <security>
      <all-permissions/>
  </security>
  <resources>
    <j2se version="1.5"/>
    <nativelib href="jws6-bugreport-native.jar"/>

<jar href="jws6-bugreport-app-1.0.jar" main="true"/>
<jar href="jws6-bugreport-jni-1.0.jar"/>

* OK. I think the nativelib element should be
*after* the jar elements. That is how it is
listed in the JNLP File Syntax here..
<http://java.sun.com/j2se/1.4.2/docs/guide/jws/developersguide/
syntax.html#resources>

JWS has also been known to be very finicky
about JNLP files, though frustratingly, it
makes a poor attempt at parsing invalid files,
and if it reports an error at all, it is usually
pointing to an entirely different element..

So, that brings me to the question..
Have you validated this JNLP file?

You might try validating it against the 1.5 DTD

<http://java.sun.com/dtd/JNLP-1.5.dtd >

Does anybody help me with that problem...?
Thanks for every hint

BTW - that was a great example you posted,
I would like to have tried it locally, but
unfortunately I do not have the immediate
means to generate the binary.

And another thing. The JNLP mentions 'bugreport'
in a number of parts. Have you actually lodged
a bug with Sun against this? Have you searched
the Bug DB for other related reports?

--
Andrew T.
PhySci.org