When I try to stop the server and restart it, I get a ExportException
java.rmi.server.ExportException: internal error: ObjID already in use
That's because you are creating a registry that already has been created (during the first start up). Just bypass call to LocateRegistry.createRegistry(_port) on the subsequent server restarts. Better yet, don't use this silly server GUI, -- it adds absolutely nothing to your project reusability or design.
On the side note, do not use underscores in variable names (except in public final static variables), here is
Java Coding Conventions
Eugene.
[ January 05, 2003: Message edited by: Eugene Kononov ]