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Bookmark "Exception in thread "main" java.lang.NoClassDefFoundError" Watch "Exception in thread "main" java.lang.NoClassDefFoundError" New topic

Exception in thread "main" java.lang.NoClassDefFoundError

preethi Ayyappan
Ranch Hand

Joined: Oct 04, 2007
Posts: 518

I am trying to run a program in a linux machine.It is in the path /usr/src/scripts.I have included mysqlconnector.jar also in that path and i gave the command

java -classpath mysql-connector-java-3.0.17-ga-bin.jar EchoClient1

to run the program.the following error occurs:

Exception in thread "main" java.lang.NoClassDefFoundError: EchoClient1
Caused by: java.lang.ClassNotFoundException: EchoClient1
at Method)
at java.lang.ClassLoader.loadClass(
at sun.misc.Launcher$AppClassLoader.loadClass(
at java.lang.ClassLoader.loadClass(
at java.lang.ClassLoader.loadClassInternal(

Am i wrong in setting path?please assist me to solve this error.

Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42958
By using an explicit "-classpath" switch you're effectively turning off the implicit "." classpath that points to the current directory. If you add that back into it, then it should work:
java -classpath .:mysql-connector-java-3.0.17-ga-bin.jar EchoClient1
Sagar Rohankar
Ranch Hand

Joined: Feb 19, 2008
Posts: 2904

One question, The java source file name is different from the class name ?
'' and you're running as 'EchoClient1'


1. Go to '/usr/src/scripts'
2. java -cp "path/mysqlconnection/jar/file/directory;.; EchoClient1

I hope there is NO 'package' defined in

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preethi Ayyappan
Ranch Hand

Joined: Oct 04, 2007
Posts: 518
Thank you ulf.Now it works well.

Hi Sagar Rohankar ,

The source and class name are have posted the wrong name by mistake.

Thank you both for your reply
I agree. Here's the link:
subject: Exception in thread "main" java.lang.NoClassDefFoundError
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