/**
     * The method is called by a ProtocolProvider implementation whenever a change in the
     * registration state of the corresponding provider had occurred.
     *
     * @param evt ProviderStatusChangeEvent the event describing the status change.
     */
    public void registrationStateChanged(RegistrationStateChangeEvent evt) {
      if (logger.isDebugEnabled())
        logger.debug(
            "The provider changed state from: " + evt.getOldState() + " to: " + evt.getNewState());

      if (evt.getNewState() == RegistrationState.REGISTERED) {
        AimConnection aimConnection = icqProvider.getAimConnection();
        aimConnection
            .getIcbmService()
            .getRvConnectionManager()
            .addConnectionManagerListener(OperationSetFileTransferIcqImpl.this);
      }
    }
  /**
   * Sends a file transfer request to the given <tt>toContact</tt> by specifying the local and
   * remote file path and the <tt>fromContact</tt>, sending the file.
   *
   * @param toContact the contact that should receive the file
   * @param file the file to send
   * @return the transfer object
   * @throws IllegalStateException if the protocol provider is not registered or connected
   * @throws IllegalArgumentException if some of the arguments doesn't fit the protocol requirements
   */
  public FileTransfer sendFile(Contact toContact, File file)
      throws IllegalStateException, IllegalArgumentException {
    assertConnected();

    if (file.length() > getMaximumFileLength())
      throw new IllegalArgumentException("File length exceeds the allowed one for this protocol");

    // Get the aim connection
    AimConnection aimConnection = icqProvider.getAimConnection();

    // Create an outgoing file transfer instance
    OutgoingFileTransfer outgoingFileTransfer =
        aimConnection
            .getIcbmService()
            .getRvConnectionManager()
            .createOutgoingFileTransfer(new Screenname(toContact.getAddress()));

    String id =
        String.valueOf(outgoingFileTransfer.getRvSessionInfo().getRvSession().getRvSessionId());

    FileTransferImpl outFileTransfer =
        new FileTransferImpl(outgoingFileTransfer, id, toContact, file, FileTransfer.OUT);

    // Adding the file to the outgoing file transfer
    try {
      outgoingFileTransfer.setSingleFile(new File(file.getPath()));
    } catch (IOException e) {
      if (logger.isDebugEnabled()) logger.debug("Error sending file", e);
      return null;
    }

    // Notify all interested listeners that a file transfer has been
    // created.
    FileTransferCreatedEvent event = new FileTransferCreatedEvent(outFileTransfer, new Date());

    fireFileTransferCreated(event);

    // Sending the file
    outgoingFileTransfer.sendRequest(new InvitationMessage(""));

    outFileTransfer.fireStatusChangeEvent(FileTransferStatusChangeEvent.PREPARING);

    return outFileTransfer;
  }