Getting Jelm operational...

**Arlof** · 07-02-2005, 12:36 AM

Hey, All..

I'll be the first to admit that I have no clue how java works. I tried following the instructions and have been fooling around with it for a couple hours and I can't get the thing going.

I've got the latest jre and when I go to run the jar file i get

Exception in thread "main" java.lang.NoClassDefFoundError: javax/comm/SerialPort
EventListener
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknow n Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)

Now if anyone could point me in the right direction that would be great.

Regards,

Arlof

**Arlof** · 07-02-2005, 03:51 AM

Well, after wasting a couple more hours I figured it out...

Apperently comm.jar and javax.comm.properties needs to be in (JRE)\lib\etc
then everything is happy!

Regards,

Arlof

**Rickertsen2** · 07-06-2005, 10:06 AM

I am not familiar with Jelm but it looks like an error with the JCA (Java Communications API). My guess is that JELM needs the JCA installed. it can be found: http://java.sun.com/products/javacom...ads/index.html

The documentation on how to install it is a bit sketchy so let my know if you have any probs.

Wait... upon reading your last post it seems you have already figured this out.

The file javax.comm.properties is part of the JCA. It basically tells java that the JCA is installed and how to use it. The JCA is a library for communication through things like serial usb and parallel ports.