Exception in thread "main" errors

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Exception in thread "main" errors

Postby chetan_123 » Mon Nov 19, 2007 6:03 am


I am getting the error "Exception in thread "main" java.lang.NoClassDefFoundError: icommand/properties", when I try to run "java -jar icommand.jar" from the command prompt.

I have set the CLASSPATH to icommand.jar and bluecove.jar correctly.

Could you please clarify the step "Put the file icommand.properties into your home directory, or your working directory." ?

I have placed the icommand.properties file in C:\

Secondly, when I use Eclipse to run RadioControl.class, it gives me the following set of errors:

No NXT address found in icommand.properties. Searching... (this may take up to a minute)
Exception in thread "main" java.lang.NoClassDefFoundError: javax/bluetooth/DiscoveryListener
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(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)
at icommand.nxt.comm.NXTCommFactory.createInstance(Unknown Source)
at icommand.nxt.comm.NXTCommand.open(Unknown Source)
at RadioControl.main(RadioControl.java:155)

I am using Windows Vista. Also, I haven't installed rxtx as mentioned in one of the posts on the forum. Please help!

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Postby bbagnall » Thu Nov 29, 2007 6:35 pm

You need to read the instructions that come with the iCommand download. There should be no reason to run java -jar icommand.jar.

Also, I suspect you might not fully understand the difference between iCommand and leJOS NXJ. They both control the NXT brick through different methods (leJOS NXJ code on the NXT brick, while iCommand operates it remotely from your PC with a Bluetooth dongle).

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