To limit no. of parameters to a Java jar, it would be nice to know if there is a default working directory where java JAR is run/expected when the JAR read/write files - in project directory path, in test_* directory below or somewhere else - if any.
We are not quite sure we understand your question. JAR files are used in Neoload usually to decode requests/responses from a server application. They are imported through the library manager, and stored in the project folder under the "lib" folder.
In what context are you referring to regarding JAR files, if I am mistaken? Could you provide more detail so we can help you?