Exception in thread "main" java.lang.NoClassDefFoundError


I am running Windows 2K SP3 with Java SDK 1.4.0.  I get this error whenever i try to run a java app.  I can get apps to compile, but not run.  Are there any suggestions on how I can correct this error?


Aaron Axelsen
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Can you post the code ? and how are running it ?
when you compile the java source file, you use

javac ClassName.java

When you run the class, you use

java ClassName

*without* the .java at the end.  It sounds like the error you get when you call

java ClassName.java

>> I can get apps to compile, but not run.  Are there any suggestions on how I can correct this error?

What is your classpath? Check it by saying,

echo %classpath%

Try adding


to the end of the classpath. So, if your classpathh is,


change it to,


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axman505Author Commented:

E:\>echo %classpath%
"E:\Program Files\Java\j2re1.4.1\lib\ext\QTJava.zip"

I changed it to:
E:\>echo %classpath%

However, this still fails to work

The program I use to write and compile code is Textpad.  Thanks again for all the assistance.

Set classpath at DOS prompt:
set classpath=%classpath%;.;

cd to the directory of class file and run the class file.
java fileName
Do not put .java or .class with file name.

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Could you post us your error, when you do java classFileName?
Mayank SAssociate Director - Product EngineeringCommented:
It might be a case problem. See that if your class name (which contains the main () method) is MyApp, then your source-file is MyApp.java, and see that when you're calling the interpreter, then you're using the correct case as:

java MyApp

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