file: Chat.java

• signIn() is used for both connecting and disconnecting. In the connect mode, "i=-1", the String contains a Chat-name. If the connection is accepted a connection_slot betwee 0 and 49 is returned.
  In the disconnect mode, "0<i<50", the String is ignored.

• broadcast() sends a Chat-message s from connection_slot "i". The server translates the slot number to its Chat-name.

• getbroadcast() is used to pole the server for a new Chat-message.

*/

import java.rmi.*;
public interface Chat extends java.rmi.Remote {
	int  signIn(String s, int i) throws java.rmi.RemoteException;
	void broadcast(String s,int i ) throws java.rmi.RemoteException;
	String getbroadcast() throws java.rmi.RemoteException;
}