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ClassNotFoundException while executing using "java -jar" command

shahabas shabeer
Ranch Hand

Joined: Feb 23, 2004
Posts: 49
I developed a java application.
My application connects to postgresql using a database driver(pg73jdbc2.jar).
The database driver jar file is there in my classpath.
My program worked as expected when I executed it using the command

java a.b.c.MyMainClass

Then I bundled my application in to a jar file.
When I tried to execute my program using the command,
java -jar MyJar.jar
it is complaining that the database Driver class(java.lang.ClassNotFoundException: org.postgresql.Driver) is not found.

I am sure that the driver jar is available in my class path and the program is working fine
when a execute it using "java a.b.c.MyMainClass" command

I also tried by copying the driver jar to my "jre/lib/ext" directory, but no luck

What could be the problem ?

Any help would be highly appreciated.

Shahabas E Shabeer
[ June 28, 2005: Message edited by: shahabas shabeer ]

The greatest pleasure in life is doing what peoples say you can not do.
Ernest Friedman-Hill
author and iconoclast

Joined: Jul 08, 2003
Posts: 24193

Jar files are 'closed.' When you use the "-jar" option, the CLASSPATH (or the -cp switch) is ignored. Putting the driver in the /ext directory ought to work, though; or you can use

java -cp MyJar.jar;pg73jdbc2.jar a.b.c.MyMainClass

[Jess in Action][AskingGoodQuestions]
Murat Balkan
Ranch Hand

Joined: Sep 10, 2002
Posts: 127
is it possible to add class files to ext folder?
I agree. Here's the link:
subject: ClassNotFoundException while executing using "java -jar" command
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