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troubleshooting Question


Avatar of kender_a
kender_a asked on
12 Comments1 Solution916 ViewsLast Modified:

I have written a program, which uses a Comm package to talk to the serial port (I'm using Sun One). It's main class is the SerialPortEventListener:

public class CTesaComm extends javax.swing.JFrame implements SerialPortEventListener {

The program build successfully, but when i try to run it, like this:

java -cp . CTesaComm

It gives this error

Exception in thread "main" java.lang.NoClassDefFoundError: javax/comm/SerialPort
        at java.lang.ClassLoader.defineClass0(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$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)

When I try to run my program without the -cp option, it gives this error:

Exception in thread "main" java.lang.NoClassDefFoundError: CTesaComm

Here's my CLASSPATH (system variable under XP):

C:\j2sdk1.4.2_04\lib\comm.jar; E:\n\kalaco\comm\app

The first one is the comm library, the latter one is the path to my program.

What am I doing wrong?

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