Anonymous User
NoClassDefFoundError: gnu/io/PortInUseException?
July 29, 2008 11:32PM
I'm just getting started. I tried installing the host software and all the required java components. When I attempt to launch reprap-host.bat, I get:

C:\cygwin\home\Greg\dev\reprap\reprap-host-20080523>java -cp ".;.\reprap.jar;C:\Program Files\Reprap\;C:\Program Files\Reprap\reprap.jar;C:\Program Files\Java\shared\*" -Xmx384M org/reprap/Main Exception in thread "main" java.lang.NoClassDefFoundError: gnu/io/PortInUseException

This sure sounds as though it is somehow not finding the rxtx libraries. Am I right? I didn't see anything in the instructions about modifying the CLASSPATH or anything. Do I need to add something?
Re: NoClassDefFoundError: gnu/io/PortInUseException?
July 30, 2008 08:09AM
Yes looks like Java cannot find the rxtx libs

I can replicate this error if I move RXTXcomm.jar out of ...lib\ext\

I presume you are using windows, double check all the three required rxtx files are in the correct place [rxtx.qbang.org]

had a problem in the past, not reprap related, with more than one version of the JRE on the same machine not sure if this is the case here
Anonymous User
Re: NoClassDefFoundError: gnu/io/PortInUseException?
July 30, 2008 11:28AM
My rxtx files:

Greg@Alice:/cygdrive/c/Program Files/Java
=>find -iname "*rxtx*" -exec ls -l {} \;
-rwxr-xr-x 1 Greg None 47421 Jul 27 10:49 ./jre1.6.0_07/bin/rxtxParallel.dll
-rwxr-xr-x 1 Greg None 77759 Jul 27 10:49 ./jre1.6.0_07/bin/rxtxSerial.dll
-rwxr-xr-x 1 Greg None 59464 Jul 27 10:42 ./jre1.6.0_07/lib/ext/RXTXcomm.jar

I think that's all the rxtx components, in their rightful places with reasonable permissions.

So is it possible my windows system isn't defaulting to the most recent jre for some reason? I have accumulated several jre's:

Greg@Alice:/cygdrive/c/Program Files/Java
=>ls
Java3D/ jre1.6.0/ jre1.6.0_03/ jre1.6.0_07/
jdk1.6.0_02/ jre1.6.0_02/ jre1.6.0_05/
Re: NoClassDefFoundError: gnu/io/PortInUseException?
July 30, 2008 09:12PM
that looks correct

try "java -version" (without speach marks smiling smiley) at the console/command prompt

will tell you which JRE version you are 'defaulting' to

sorry other than that don't have any ideas
Hi everybody!

I have the same problem with my reprap-host.
I tryed to look, what version of jre does my windows use, but the window(where it should be shown) momentally disapears.

sorry for my english)) (i'm from Ukraine)
Anonymous User
Re: NoClassDefFoundError: gnu/io/PortInUseException?
August 23, 2008 11:04AM
I was able to solve this problem by uninstalling my JDK along with all the different JRE versions on my system, then installing a fresh JDK and the latest JRE, and then re-applying the components needed for RepRap.
Re: NoClassDefFoundError: gnu/io/PortInUseException?
August 23, 2008 11:30AM
baster.89 - dont apologise for your english - its far far better than my ukrainian.
(I assume that is what your 'native' language is - mine in UK english.)
Thanks to everybody, but the problem remained...(
I tried to delete and reinsatall the JDK and JRE, but nothing has helped.((
Richard Benjamin:
I spoke english much much better some years ago. But now I forgot it, and can translate only one way easily (to russian). And translation to english is very hard for me now(..
Re: NoClassDefFoundError: gnu/io/PortInUseException?
January 17, 2010 12:31PM
I'm having the same problem. My java version is 1.6.0_17, according to java -version. Granted, 1.6.0_17 is not My default java version; 1.5.0_22 is. However, 1.6.0_17 is the binary invoked by the sh script.

Any additional tips would be greatly appreciated.
Any updates to this post? I have Java JDE 6 installed, but my "java -version" lookup brings back:

java version "1.3.1_01"
Java(TM) 2 Runtime Environment
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