/**
   * Sends the given instant message through this chat transport, by specifying the mime type (html
   * or plain text).
   *
   * @param message The message to send.
   * @param mimeType The mime type of the message to send: text/html or text/plain.
   * @throws Exception if the send operation is interrupted
   */
  public void sendInstantMessage(String message, String mimeType) throws Exception {
    // If this chat transport does not support instant messaging we do
    // nothing here.
    if (!allowsInstantMessage()) return;

    OperationSetBasicInstantMessaging imOpSet =
        contact.getProtocolProvider().getOperationSet(OperationSetBasicInstantMessaging.class);

    Message msg;
    if (mimeType.equals(OperationSetBasicInstantMessaging.HTML_MIME_TYPE)
        && imOpSet.isContentTypeSupported(OperationSetBasicInstantMessaging.HTML_MIME_TYPE)) {
      msg =
          imOpSet.createMessage(
              message, OperationSetBasicInstantMessaging.HTML_MIME_TYPE, "utf-8", "");
    } else {
      msg = imOpSet.createMessage(message);
    }

    if (contactResource != null) imOpSet.sendInstantMessage(contact, contactResource, msg);
    else imOpSet.sendInstantMessage(contact, ContactResource.BASE_RESOURCE, msg);
  }