private ParticipantId computeCreator(WaveViewData wave) {
   for (ObservableWaveletData wavelet : wave.getWavelets()) {
     if (IdUtil.isConversationRootWaveletId(wavelet.getWaveletId())) {
       return wavelet.getCreator();
     }
   }
   // If not found creator - compare with UNKNOWN_CREATOR;
   return UNKNOWN_CREATOR;
 }