code: public NiftyClientChannel getNiftyChannel(Object client)
      {
          try {
              return NiftyClientChannel.class.cast(getRequestChannel(client));
          }
          catch (ClassCastException e) {
              throw new IllegalArgumentException("The swift client uses a channel that is not a NiftyClientChannel", e);
          }
      }
docs: Returns the {@link NiftyClientChannel} backing a Swift client
  
  @throws IllegalArgumentException if the client is not using a {@link com.facebook.nifty.client.NiftyClientChannel}
  
  @deprecated Use {@link #getRequestChannel} instead, and cast the result to a {@link NiftyClientChannel} if necessary