docs: public boolean isFullyEstablished() {
          boolean result = true;
  
          MediaNegotiator mediaNeg = getMediaNegotiator();
          if ((mediaNeg == null) || !mediaNeg.isFullyEstablished()) {
              result = false;
          }
  
          TransportNegotiator transNeg = getTransportNegotiator();
          if ((transNeg == null) || !transNeg.isFullyEstablished()) {
              result = false;
          }
  
          return result;
      }