Edward Harned

What do you mean by "run in the same sequence as it ran in my JVM?"

Do you mean one runs to completion. Then two starts and runs ....

In such a case why bother with threads.

Everything you can do on a command line you can do with the Run Configurations.

Just open Run Configurations and add the jar file pointer there.

no

My first suggestion is to search the forum for similar problems. You're about the millionth person to ask this question.

Next look into classpath.

Now it gets interesting.

RMI is a single session -- A contacts B, B responds to A. Done

What you want is sessions going both ways. B, the service, can send messages to A, C, D, etc.

In order to do that, the clients need to become RMI servers. This is very similar to RMI callback -- the clients need to implement a Remote interface, so the server can call them back. There are examples here to do that. There are tutorials on the internet, etc.

Once you do it once, it becomes simple.

The simple answer is: There is no API to identify a particular caller. Do it yourself.

How? Pass a string, or some id at sign-on time to associate a user and continue to pass that id for every call thereafter.

How else? You said you didn't like the other complex methods, so innovate.

I've been doing RMI since release 1.1. I gave you a policy file that works. Use it. Other people have been using the tutorial for over a decade. Perhaps the problem is not with the tutorial.

Try using the file I gave you with: permission java.security.AllPermission "", "";

The RMI Registry is a Java program and also needs a permission file.

You have a permission problem. The "all" permission policy works for ALL permissions. So java isn't finding your policy file. When java doesn't find a policy file it never says so, it just craps out. Look further into finding the file.

How about just keeping a list of callers yourself.

You need to have a policy file with RMI, such as:
grant { permission java.security.AllPermission "", ""; };
and on your script add: -Djava.security.policy=%WHERE YOU PUT IT%\Security\policy.all

Are you looking for a Fork/Join solution? F/J works well with recursion. Perhaps this article I wrote may help: A Java Fork-Join Conqueror

Please read this: http://sscce.org/

Now the problem is not with all that code. The problem is with your script.
CLASSPATH is probably the problem. The client, server and RMI Registry all need access to the classes.
For local testing it is easiest to have every class on the CLASSPATH.
Then when all is working, you can separate classes.

Keep looking. Nothing happens by magic.