Multiple Remote Interfaces

Remote objects can have multiple Remote interfaces.
The example below, a minimal modification of the Hello World application, illustrates a remote object with 2 Remote interfaces: Hello and Goodbye.
New or modified data appears in red.
The new files, Goodbye.java and GoodbyeClient.java, are very much like Hello.java and HelloClient.java, respectively.
The modified file is HelloImpl.java, to implement the Goodbye interface.

import java.rmi.Remote;
import java.rmi.RemoteException;

public interface Goodbye extends Remote {

String sayGoodbye() throws RemoteException;
}

import java.rmi.Naming;
import java.rmi.RemoteException;
import java.rmi.RMISecurityManager;
import java.rmi.server.UnicastRemoteObject;

public class HelloImpl extends UnicastRemoteObject
implements Hello, Goodbye

{

public HelloImpl() throws RemoteException { }

    public String sayHello() {
            return "Hello World!";
        }

    public String sayGoodbye() {
            return "Goodbye World!";
        }

public static void main(String args[]) {

        try {
            HelloImpl obj = new HelloImpl();
            Naming.rebind("HelloServer", obj);
            System.out.println("HelloServer bound in registry");
            } catch (Exception e) {
                 System.out.println("HelloServer err: " + e.getMessage());
                 e.printStackTrace();
            }
       }
}

import java.rmi.Naming;
import java.rmi.RemoteException;public class GoodbyeClient { public static void main(String arg[]) { String message = "blank"; try {

            Goodbyeobj = (Goodbye) Naming.lookup("rmi://"
                + "lysander.cs.ucsb.edu"
                + "/HelloServer");
            System.out.println(obj.sayGoodbye());
        } catch (Exception e) {
            System.out.println("GoodbyeClient exception: " + e.getMessage());
            e.printStackTrace();
        }
    }
}