docs: public void getFeature(int lat, int lon) {
      info("*** GetFeature: lat={0} lon={1}", lat, lon);
  
      Point request = Point.newBuilder().setLatitude(lat).setLongitude(lon).build();
  
      Feature feature;
      try {
        feature = blockingStub.getFeature(request);
        if (testHelper != null) {
          testHelper.onMessage(feature);
        }
      } catch (StatusRuntimeException e) {
        warning("RPC failed: {0}", e.getStatus());
        if (testHelper != null) {
          testHelper.onRpcError(e);
        }
        return;
      }
      if (RouteGuideUtil.exists(feature)) {
        info("Found feature called \"{0}\" at {1}, {2}",
            feature.getName(),
            RouteGuideUtil.getLatitude(feature.getLocation()),
            RouteGuideUtil.getLongitude(feature.getLocation()));
      } else {
        info("Found no feature at {0}, {1}",
            RouteGuideUtil.getLatitude(feature.getLocation()),
            RouteGuideUtil.getLongitude(feature.getLocation()));
      }
    }