cdm/src/main/java/ucar/nc2/ft/remote/CdmrFeatureDataset.java
public static FeatureType isCdmrfEndpoint(String endpoint) throws IOException {

    HTTPSession httpClient = HTTPFactory.newSession(endpoint);
    String url = endpoint + "?req=featureType";

    // get the header
    try (HTTPMethod method = HTTPFactory.Get(httpClient, url)) {
      method.setFollowRedirects(true);
      int statusCode = method.execute();
      if (statusCode != 200) return null;
      String content = method.getResponseAsString();
      return FeatureType.getType(content);

    } catch (Throwable t) {
      t.printStackTrace();
      return null;
    }
  }
public static FeatureType isCdmrfEndpoint(String endpoint) throws IOException {

    HTTPSession httpClient = HTTPFactory.newSession(endpoint);
    String url = endpoint + "?req=featureType";

    // get the header
    try (HTTPMethod method = HTTPFactory.Get(httpClient, url)) {
      method.setFollowRedirects(true);
      int statusCode = method.execute();
      if (statusCode != 200) return null;
      String content = method.getResponseAsString();
      return FeatureType.getType(content);

    } catch (Throwable t) {
      t.printStackTrace();
      return null;
    }
  }
all CdmrFeatureDatasets must return their featureType - use as a fail-fast test of the endpoint