Another little jRtaiLab bug?

Stienen, A.H.A. (CTW) a.h.a.stienen at
Mon Jan 16 14:54:47 CET 2006

Hello Marco,

There might be yet another little bug. I can now execute 'java -jar 
jRtaiLab.jar', press the connect button, but after entering the server 
details and pressing connect, it throws out another exception error (see 

I can still run it from IE though, as applet from my five line HTML 
file. However, it doesn't connect anymore. It doesn't given an error 
like above and behaves more or less like it should (closes the connect 
button and waits), but it just sits there and never tells me it is (or 
isn't) connected to the server.

Just as a check, I went to your RTAI-XML page and started the jRtaiLab 
applet from there (naturally using the same computer). It worked just 
fine; it connected to my running RTAI model and showed all the 
parameters and signals.

So whats going on? I copied all the files from the java_files dir to my 
own computer, and it just refuses to connect...

Kind regards,


C:\Documents and Settings\Arno Stienen\Desktop\jrtailab>java -jar 
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: 
         at Target.connect(
         at jRtaiLab.Connect(
         at ConnectFrame.connect(
         at ConnectFrame.access$0(
         at ConnectFrame$1.mouseClicked(
         at java.awt.AWTEventMulticaster.mouseClicked(Unknown Source)
         at java.awt.Component.processMouseEvent(Unknown Source)
         at javax.swing.JComponent.processMouseEvent(Unknown Source)
         at java.awt.Component.processEvent(Unknown Source)
         at java.awt.Container.processEvent(Unknown Source)
         at java.awt.Component.dispatchEventImpl(Unknown Source)
         at java.awt.Container.dispatchEventImpl(Unknown Source)
         at java.awt.Component.dispatchEvent(Unknown Source)
         at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown 
         at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
         at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
         at java.awt.Container.dispatchEventImpl(Unknown Source)
         at java.awt.Window.dispatchEventImpl(Unknown Source)
         at java.awt.Component.dispatchEvent(Unknown Source)
         at java.awt.EventQueue.dispatchEvent(Unknown Source)
java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)

         at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown 
         at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
         at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
         at Source)

Marco Romagnoli wrote:
> Hello Arno,
> you've found a little bug in jRtaiLab!! Precisely not in jRtaiLab, but 
> in the applet that let you use it through internet. If the applet, 
> looking for some parameters, didn't find its parent (the browser) it 
> throwed an exception (that it was the reason why jRtaiLab didn't start). 
> I've corrected this little bug so new version (1.0.2) is on our server 
> and you can use it by command line 
> java -jar jRtaiLab.jar

  /  |_| <<< IR. ARNO H.A. STIENEN >>>
|_ O  | Biomechanical Engineering |
|_|__/  a.h.a.stienen at  | +31-(0)53-489-4778
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