Distributed computing] How to let a class act both a server and client?

[jkert]

I am imlementing a didtributed banking system.
There are 4 bank branchs need to communicate to each other ,get balance and transfer money from one branch to another, so they need to act both as a server and client?

I know how to write a program in a standard client communicates to server and server respond to cliemt but I have no idea how to let them both act as a server and client.

And if I use socket, the client (or server) will just send a stream to server, so how could the server (or client) know what's kind of operation he need to do?

Anyone know how to do it? Please help me.

thanks

[ArchAngel]

You've got loads of ways you could implement this.

From your post, I'm assuming you're not going to use RMI.

If so, then it might be worth creating a little protocol for your system to use. For example, the first word use in the communication is the operation required, following by its details. For example:

BALANCE
SEND 32155
RECEIVE 2132

The first command asks for the balance of the branch that the command is sent to. The second command requests the transfer £321.55 *to* the branch that the command is sent to. The third command requests the transfer of £21.32 *from* the branch tha the command is sent to.

[jkert]

If I use RMI, how should I do to let a class both act as a server and client?

[ArchAngel]

If you haven't done RMI before I wouldn't recommend it to do this coursework - it takes a bit of getting used to. Sockets will do fine.