ClientConsole.java

// This file contains material supporting section 3.7 of the textbook:
// "Object Oriented Software Engineering" and is issued under the open-source
// license found at www.lloseng.com 

import java.io.*;
import client.*;
import common.*;

/**
 * This class constructs the UI for a chat client.  It implements the
 * chat interface in order to activate the display() method.
 * Warning: Some of the code here is cloned in ServerConsole 
 *
 * @author François Bélanger
 * @author Dr Timothy C. Lethbridge  
 * @author Dr Robert Laganière
 * @version July 2000
 */
public class ClientConsole implements ChatIF 
{
  //Class variables *************************************************
  
  /**
   * The default port to connect on.
   */
  final public static int DEFAULT_PORT = 5555;
  
  //Instance variables **********************************************
  
  /**
   * The instance of the client that created this ConsoleChat.
   */
  ChatClient client;

  
  //Constructors ****************************************************

  /**
   * Constructs an instance of the ClientConsole UI.
   *
   * @param host The host to connect to.
   * @param port The port to connect on.
   * @param loginID The loginID user gave
   */
  public ClientConsole(String host, int port, String loginID) 
  {
    try 
    {
      client= new ChatClient(host, port, this, loginID);
    } 
    catch(IOException exception) 
    {
      System.out.println("Error: Can't setup connection!"
                + " Terminating client.");
      System.exit(1);
    }
  }

  
  //Instance methods ************************************************
  
  /**
   * This method waits for input from the console.  Once it is 
   * received, it sends it to the client's message handler.
   */
  public void accept() 
  {
    try
    {
      BufferedReader fromConsole = 
        new BufferedReader(new InputStreamReader(System.in));
      String message;

      while (true) 
      {
        message = fromConsole.readLine();
        client.handleMessageFromClientUI(message);
      }
    } 
    catch (Exception ex) 
    {
      System.out.println
        ("Unexpected error while reading from console!");
    }
  }

  /**
   * This method overrides the method in the ChatIF interface.  It
   * displays a message onto the screen.
   *
   * @param message The string to be displayed.
   */
  public void display(String message) 
  {
    System.out.println("> " + message);
  }

  
  //Class methods ***************************************************
  
  /**
   * This method is responsible for the creation of the Client UI.
   *
   * @param args[0] The host to connect to.
   */
  public static void main(String[] args) 
  {
    String host = "";
    int port = 0;  //The port number
    String loginID = "";

    //Checks if the first argument is a loginID
    try{
      loginID = args[0];
    }catch(ArrayIndexOutOfBoundsException e){
      System.out.println("No login ID detected, program will not exit.");
      System.exit(0);
    }

    //Saves the inputted host or uses default if non is given
    try{
      host = args[1];
    }
    catch(ArrayIndexOutOfBoundsException e){
      host = "localhost";
    }

    //Saves the inputted port or uses default if non is given
    try{
      port = Integer.parseInt(args[2]); //Get port from command line
      ClientConsole chat= new ClientConsole(host, port, loginID);
      chat.accept();
    }
    catch(Throwable t){
      ClientConsole chat= new ClientConsole(host, DEFAULT_PORT, loginID); //Set port to 5555
      chat.accept();
    }
  }
}
//End of ConsoleChat class