// Add client
//
// Usage: AddClient [URL]
//
// The server hostname and port number are obtained from a web server.
// If URL is not specified, a default URL is used.
//
// Uses RMI to communicate with a server which implements the Add interface
// to add two integers.  Uses KeyClient to establish an authenticated login
// to the server.
//
// R. Perry, July 1998

import java.io.*;
import java.rmi.*;
import java.net.*;

public class AddClient {

  public static void main( String args[])
    throws Exception
  {
    String url = "http://acadia.ee.vill.edu/~perry/research/rsa/port";

    if( args.length > 0)
      url = args[0];

    System.out.println( "AddClient: using URL: " + url);

    URL u = new URL( url);
    BufferedReader in = new BufferedReader( new InputStreamReader( u.openStream()));

  // The server hostname and port number should be returned by the URL
  //
    String server = in.readLine();
    int port = Integer.parseInt(in.readLine());
    in.close();

  // Initialize Key Client
  //
    String service = "AddServer";

    KeyClient K = new KeyClient( server, port, service);

  // connect to service
  //
    String rmi = "rmi://" + server + ":" + port + "/" + service + "-" + K.getKey();

    System.out.println( "AddClient: contacting " + rmi);

    Add A = (Add) Naming.lookup( rmi);

  // try to perform an addition - should fail since we didn't login yet
  //
    int x = 1, y = 1, z;

    z = A.add( x, y, 123);	// junk sequence number

    System.out.println( "AddClient: " + service + " says " + x + " + " + y + " = " + z);

  // login - should get username:password interactively from the user...
  //
    String auth = "frodo:abc";

    if( ! K.login( auth))
      System.out.println( "AddClient: login() failed.");

  // perform some additions
  //
    z = A.add( x, y, K.seqnum());

    System.out.println( "AddClient: " + service + " says " + x + " + " + y + " = " + z);

    ++x; ++y;

    z = A.add( x, y, 99999);	// junk sequence number, should fail

    System.out.println( "AddClient: " + service + " says " + x + " + " + y + " = " + z);

    ++x; ++y;

    z = A.add( x, y, K.seqnum());

    System.out.println( "AddClient: " + service + " says " + x + " + " + y + " = " + z);
  }
}