code: public static String getHost(final URI uri) throws NormalizationException {
          final String host = Strings.emptyToNull(uri.getHost());
          if (host == null) {
              throw new NormalizationException(uri.toString(), "No host in URI");
          }
          return host;
      }
docs: Returns the host of the given URI or throws an exception if the URI has no host.
  
  @param uri the URI to extract the host from
  @return the extracted host
  @throws NormalizationException if there is no host for the given uri