public void update(Observable source, Object object) {
    if (source instanceof Users) {
      if (!this.isDisabled()) {
        try {
          Operations.sendUserNamesList(users.getUserNames(), out);
        } catch (IOException io) {
          logger.error("IO Exception", io);
        }
      }
    }

    if (source instanceof Messages) {
      try {
        Operations.sendMessage((MessageType) object, out);
      } catch (IOException io) {
        if (out != null) {
          try {
            out.close();
          } catch (Exception ioe) {
            logger.error("Failed to close the output stream", ioe);
          }
        }

        logger.error("Impossible to send messages", io);
      }
    }
  }
  public ClientThread(Socket socket, History history, Users users) throws IOException {

    logger.warn("New client is trying to connect to the chat...");
    logger.info("Assigning a socket to a new client...");
    this.s = socket;

    logger.info("Getting the input stream...");
    in = new DataInputStream(s.getInputStream());

    logger.info("Getting the output stream...");
    out = new DataOutputStream(s.getOutputStream());

    this.users = users;
    users.addObserver(this);

    this.history = history;

    start();
    logger.warn("Connection with new user is established.");
  }
 public void run() {
   try {
     prepareClient();
     logger.info("Starting normal session with " + getClientName());
     while (true) {
       this.receive();
     }
   } catch (IOException ioe) {
     logger.warn("Client " + this + " has been disconnected.");
     this.setDisabled(true);
     users.remove(this);
   } finally {
     try {
       if (s != null && !s.isClosed()) {
         s.close();
         logger.warn("Socket with " + this + " has been closed.");
       }
     } catch (IOException ioe) {
       logger.error("Socket has not been closed.", ioe);
     }
   }
 }
  private void prepareClient() throws IOException {
    logger.info("Waiting for client's name");
    Message mes = Operations.receive(in);
    setClientName((String) mes.getValue());
    logger.info("Username for " + s.getInetAddress() + " received: " + userName);

    users.add(this);
    logger.info("User " + getClientName() + " has been added to the userlist.");

    messages = new Messages();
    logger.info("Message list created");

    if (!history.containsKey(userName)) {
      history.put(userName, messages);
    } else {
      messages = history.get(userName);
    }
    messages.addObserver(this);
    logger.info("Message list assigned to history");

    logger.info("Sending the list of users.");
    Operations.sendUserNamesList(users.getUserNames(), out);
    logger.info("Userlist has been sent");
  }
  public void receive() throws IOException {
    Message message = Operations.receive(in);
    logger.info("New message received.");

    processMessage(message);
  }
public class ClientThread extends Thread implements Observer, ServerInterface {
  private Socket s = null;
  private DataInputStream in = null;
  private DataOutputStream out = null;
  private Users users;
  private static final Logger logger = Logger.getLogger("im.server");
  private History history;
  private String userName = "******";
  private Messages messages = null;
  private boolean disabled = false;

  public ClientThread(Socket socket, History history, Users users) throws IOException {

    logger.warn("New client is trying to connect to the chat...");
    logger.info("Assigning a socket to a new client...");
    this.s = socket;

    logger.info("Getting the input stream...");
    in = new DataInputStream(s.getInputStream());

    logger.info("Getting the output stream...");
    out = new DataOutputStream(s.getOutputStream());

    this.users = users;
    users.addObserver(this);

    this.history = history;

    start();
    logger.warn("Connection with new user is established.");
  }

  public void run() {
    try {
      prepareClient();
      logger.info("Starting normal session with " + getClientName());
      while (true) {
        this.receive();
      }
    } catch (IOException ioe) {
      logger.warn("Client " + this + " has been disconnected.");
      this.setDisabled(true);
      users.remove(this);
    } finally {
      try {
        if (s != null && !s.isClosed()) {
          s.close();
          logger.warn("Socket with " + this + " has been closed.");
        }
      } catch (IOException ioe) {
        logger.error("Socket has not been closed.", ioe);
      }
    }
  }

  public void receive() throws IOException {
    Message message = Operations.receive(in);
    logger.info("New message received.");

    processMessage(message);
  }

  private void processMessage(Message message) throws IOException {
    if (message.getType().equals("SimpleMessage")) {
      MessageType messageType = (MessageType) message.getValue();
      String receiver = messageType.getToUser();
      history.get(receiver).add(messageType);
    }

    if (message.getType().equals("ConnectUserMessage")) {
      String user = (String) message.getValue();
      Messages messages = history.get(user);
      Operations.sendHistory(messages.getLastFiveWith(user), out);
    }
  }

  // public void send(MessageType message) throws IOException {
  // Operations.sendMessage(message, out);
  // }

  public String toString() {
    return getClientName() + " [" + s.getInetAddress() + "]";
  }

  public String getClientName() {
    return userName;
  }

  public void update(Observable source, Object object) {
    if (source instanceof Users) {
      if (!this.isDisabled()) {
        try {
          Operations.sendUserNamesList(users.getUserNames(), out);
        } catch (IOException io) {
          logger.error("IO Exception", io);
        }
      }
    }

    if (source instanceof Messages) {
      try {
        Operations.sendMessage((MessageType) object, out);
      } catch (IOException io) {
        if (out != null) {
          try {
            out.close();
          } catch (Exception ioe) {
            logger.error("Failed to close the output stream", ioe);
          }
        }

        logger.error("Impossible to send messages", io);
      }
    }
  }

  private void setDisabled(boolean state) {
    this.disabled = state;
  }

  private boolean isDisabled() {
    return this.disabled;
  }

  private void setClientName(String userName) {
    this.userName = userName;
  }

  private void prepareClient() throws IOException {
    logger.info("Waiting for client's name");
    Message mes = Operations.receive(in);
    setClientName((String) mes.getValue());
    logger.info("Username for " + s.getInetAddress() + " received: " + userName);

    users.add(this);
    logger.info("User " + getClientName() + " has been added to the userlist.");

    messages = new Messages();
    logger.info("Message list created");

    if (!history.containsKey(userName)) {
      history.put(userName, messages);
    } else {
      messages = history.get(userName);
    }
    messages.addObserver(this);
    logger.info("Message list assigned to history");

    logger.info("Sending the list of users.");
    Operations.sendUserNamesList(users.getUserNames(), out);
    logger.info("Userlist has been sent");
  }
}