Can you add multiple jars in a jar file and then launch that jar file

Another option is to use a custom class loader such as this one:

http://one-jar.sourceforge.net/

Merge your jars to one jar. See this thread.

You need to be careful when doing this. If the jars you are merging have manifest files with critical information - these can get lost, only the last file will get merged.

E.g. If you merge JavaMail - the manifest file is important. If you lose it - bad things csn happen.

The safest thing to do is to look at each jar file and check the manifest file.