Making the
Server Class
A
full chat program will have client classes that is installed on our PCs
send messages to a server, or controller class on one computer. This
controller class will then broadcast the messages back out to the clients.
- Given this two way communication, this is more of a peer-to-peer network than a client-server network. Each client acts as a server, and the server acts as a client, when it broadcasts messages to the clients.
- That may be a shake too complex for our first application, so let's just make a bulletin board program to start. In this program, the clients will post messages to the server, which will simply display them in a bulletin-board manner. We can easily extend this later to be a full fledged chat application.
- Our class must extend UnicastRemoteObject, and implement our interface Chat. Once we implement the interface, we must provide implementations for each of the methods.
- public void Login (String user, String password) Authenticate the user. We could use some type of file, perhaps encrypted, to do this. Or we could connect to a database and query the username and password against that. Time permitting, we'll do that. But for now, let's simply compare the user and password to some hardcoded values.
- public void sendMessage(String message, String user) The message is what we want to display on the bulletin board. Once we make a full chat program, we can direct the message to a specific user. But for now, let's just add messages to a JList when the user equals "board".