External Jar files packaged with the Application Jar.

Question

Hello Friends,
I have a Java class 'Config.java' with a package a.b.c
This class requires a third party Jar 'new.jar'. I place this Jar file in the parent directory of the package.
So I can compile the Config.java with classpath as '.'
This works fine.
Now while packaging them, I create a mymanifest.mf file with following contents
Main-Class: a.b.c.Config
Class-Path: . new.jar
and issue the command
jar -cvmf mymanifest.mf myjar.jar *
This creates a jar file with appropriate manifest information and heirarchy (since the included third party jar is in the same directory)
When I run the Jar by issuing the command
java -jar myjar.jar
It gives me an error, NoClassDefFound for a class inside the included third party jar.
I have gone through some of the other queries posted in this forum and through Sun's articles for creating Jar files.
I have taken care of all the minute things involved in writing the manifest file, etc.
I dont understand why such a simple application gives me a problem.
Am I still missing something ?
Regards,
Ravi

Answer 1

I had the same problem. But I solve it.. The thing that you have to do is:
create another directory in your project application directory let's say your project directory is Project. such as Project / lib.
then put external jars in lib directory.
The last thing you have to do :
change your manifest file like that
Main-Class : mainclass
Class-Path : lib/externaljar1.jar lib/externaljar2.jar
I don't know you ever deal with manifest files before but there can be very stupid errors while you create .
i.e there should be a space between ":" and mainclass name you shoul use "/" not "\" etc.
I think it will work for you.