/*
 * Networked Wire, Server Side
 * 
 * $Id: ServerWire.java,v 1.2 2003/10/28 21:41:15 gus Exp $
 *
 * Developed for "Rethinking CS101", a project of Lynn Andrea Stein's AP Group.
 * For more information, see <a href="http://www.ai.mit.edu/projects/cs101/">the
 * CS101 homepage</a> or email <las@ai.mit.edu>.
 *
 * Copyright (C) 1996 Massachusetts Institute of Technology.
 * Please do not redistribute without obtaining permission.
 */
package cs101.net;

import cs101.awt.ServerDialog;
import java.io.*;
import java.net.*;

/**
 * Networked Wire, Server Side.  Provides readObject, writeObject.
 * <p>
 *
 * If server's port is not provided at creation time, the user
 * is prompted for this information using ServerDialog.
 * <p>
 * Copyright 1996 Massachusetts Institute of Technology
 *
 * @see      cs101.net.Wire
 * @see      cs101.net.ClientWire
 *
 * @author   Todd C. Parnell, tparnell@ai.mit.edu
 * @author   Maciej Stachowiak, maciej@ai.mit.edu 
 * @author   Lynn Andrea Stein, las@ai.mit.edu
 * @version  $Id: ServerWire.java,v 1.2 2003/10/28 21:41:15 gus Exp $
 *
 */

public class ServerWire implements Wire {

  /** 
   * The network connection.  Contains all of the relevant connect
   * info, if we need it 
   */
  private Socket sock;
  /** Where to read from */ 
  private ObjectInputStream in;
  /** Where to write to */
  private ObjectOutputStream out;
  /** Spew to System.out? */
  private boolean verbose;
  
  /**
   * How to make one, if we know the port.  Control verbosity.
   *
   * @param port    the port number to listen on
   * @param verbose toggle verbosity
   */
  public ServerWire( int port, boolean verbose ) {
    this.verbose = verbose;
    this.connectTo( port );
  }
  
  
  /**
   * How to make one, if we know the port.  Verbose mode.
   *
   * @param port      the port number to listen on
   */
  public ServerWire( int port ) {
    this(port, true);
  }

  /**
   * How to make one, if we don't know who we want to talk to.
   * Uses ServerDialog to ask user.  Verbose mode.
   */
  public ServerWire() {    
    this.verbose = true;
    ServerDialog qd = new ServerDialog();
    qd.ask();
    this.connectTo( qd.getPort() );
  }
  
  /**
   * Opens a connection to a server presumed to be listening on hostName,
   * port.  Sets up listener thread.  Called by constructor; should not be
   * called otherwise.
   *
   * @param port      the port number on which the server is listening
   */
  protected void connectTo( int port ) {
    if (this.verbose) System.out.println("Server:  listening on port " + port); 
    try {
      ServerSocket srv = new ServerSocket( port );
      this.sock = srv.accept();
      this.in = new ObjectInputStream( this.sock.getInputStream() );
      this.out = new ObjectOutputStream( this.sock.getOutputStream() );
    } catch (IOException e) {
      throw new RuntimeException("Server:  " +
				 "can't establish communication on port " + port );
    }
  }

  /**
   * Use this to read an Object from the Wire.
   *
   * @return the Object read.
   */
  public Object readObject() {
    try {
      return this.in.readObject();
    }
    catch (Exception e) {
      throw new RuntimeException("ServerWire:  failed to read."); 
    }
  }
  
  /**
   * Use this method to write an Object to the Wire.
   *
   * @param o The object to be written.
   */
  public void writeObject( Object o ) {
    try {
      this.out.writeUnshared( o );
    } catch (IOException e) {
      throw new RuntimeException("ServerWire:  failed to write."); 
    }
  }
  
  /**
   *  Closes the Socket.
   */
  
  public void finalize() {
    try {
      this.in.close();
      this.out.close();
      this.sock.close();
    } catch (IOException e) {}
  }
}


/* Comments:
 *
 * History:
 *     $Log: ServerWire.java,v $
 *     Revision 1.2  2003/10/28 21:41:15  gus
 *     use writeUnshared not writeObject to avoid confusing communication problems
 *
 *     Revision 1.1.1.1  2002/06/05 21:56:32  root
 *     CS101 comes to Olin finally.
 *
 *     Revision 1.8  1999/02/17 17:36:47  tparnell
 *     added verbosity option
 *
 *     Revision 1.7  1999/01/20 22:28:05  tparnell
 *     left in a println.  oops
 *
 *     Revision 1.6  1999/01/20 22:24:55  tparnell
 *     Modified ordering on creation of input/outputStreams
 *
 *     Revision 1.5  1998/10/16 19:46:04  tparnell
 *     Fixed javadoc returns to return
 *
 *     Revision 1.4  1998/07/24 17:13:46  tparnell
 *     Placate new javadoc behavior
 *
 *     Revision 1.3  1998/07/23 14:58:15  tparnell
 *     javadoc fix
 *
 *     Revision 1.2  1998/07/22 18:18:08  tparnell
 *     move from util to net
 *
 *     Revision 1.1  1998/06/24 16:32:20  tparnell
 *     changes after summer98.  added a multi-user Group server and some
 *     other misc files
 *
 *
 */