I heard some people said "standalone" mode, what does it mean?
and, I think non-network mode should not involve with lock/unlock,am I right?
When you submit your assignment, each part (client and server) must be executable using a command of this exact form:
java -jar <path_and_filename> [<mode>]
The mode flag must be either "server", indicating the server program must run, "alone", indicating standalone mode, or left out entirely, in which case the network client and gui must run.
"alone" means non-network mode, "server" means network mode for starting up the server, "empty" means network mode for starting up the client.
In order to use the same server side programs, I allowed the lock operations for both modes. But this depends on how you make your decisions.
Hope this help.