code: public void setBroadcastLayout(String broadcastId, BroadcastProperties properties) throws OpenTokException {
          if (StringUtils.isEmpty(broadcastId) || properties == null) {
              throw new InvalidArgumentException("BroadcastId is not valid or properties are null");
          }
          this.client.setBroadcastLayout(broadcastId, properties);
      }
docs: Sets the layout type for the broadcast. For a description of layout types, see
  <a href="hhttps://tokbox.com/developer/guides/broadcast/live-streaming/#configuring-video-layout-for-opentok-live-streaming-broadcasts">Configuring
  video layout for OpenTok live streaming broadcasts</a>.
  
  @param broadcastId {String} The broadcast ID.
  
  @param properties This BroadcastProperties object that defines layout options for
  the broadcast.