To run the OCSF tester, you must first install ocsf, and make sure ocsf is in your classpath (or is a subdirectory of ocsftester).
Then you must compile the six .java files.
To execute the code, first go to the directory that is the parent directory to ocsftester.
To run the tester you must first start a server. You can either start a manually controlled server: "java ocsftester/ServerFrame", or a server that will periodically and automatically change state in order to exercise the various features of OCSF: "java ocsftester/ServerDriver".
Next you must start one or more clients. You can start an individual client using: "java ocsftester/ClientFrame". Or you can start a test driver that will automatically start clients, kill them, send messages etc.: "java ocsftester/ClientsFrame".
To learn how this code works, consult the book "Object-Oriented Software Engineering: Practical Software Development using UML and Java" by Lethbridge and Laganière.