private void notifyExchangeStopped() {
    for (IExchangeViewerListener listener : exchangeViewerListeners) {
      listener.setExchangeStopped();
    }

    for (IExchangesStoreListener listener : exchangesStoreListeners) {
      listener.setExchangeStopped(this);
    }
  }
 public void setRequest(Request request) {
   this.request = request;
   if (this.request != null) {
     this.request.setErrorMessage(errMessage);
   }
   for (IExchangeViewerListener listener : exchangeViewerListeners) {
     listener.addRequest(request);
   }
 }
  public void setResponse(Response res) {
    response = res;
    if (response != null) {
      response.setErrorMessage(errMessage);
    }

    for (IExchangeViewerListener listener : exchangeViewerListeners) {
      listener.addResponse(res);
    }
  }
 public void informExchangeViewerOnRemoval() {
   for (IExchangeViewerListener listener : exchangeViewerListeners) {
     listener.removeExchange();
   }
 }