Java APIs

Hi All.

I have been given a task where I have been asked to implement a Java RMI version of an SFTP (Simple File Transfer Protocol) Client / Server. It must use the following commands:

list - list files in current directory
cd - change directory
get filename - copy file from server to client
put - upload file from client to server
bye - close connection

In essence, a FTPServer Factory has to be created which i'm guessing would use the rmi registry to handle requests between the client and server.

I just can't seem to grasp how this would work using RMI, any ideas / assistance would be appreciated.

Thanks