code: public static String getDidYouMeanMessage(Iterable<String> allNames, String wrongName) {
      String closestName = getClosest(allNames, wrongName);
      if (closestName != null) {
        return String.format(" Did you mean '%s'?", closestName);
      }
      return "";
    }
docs: Given a collection of strings and a name that isn't contained in it. Return a message that
  suggests one of the names.
  
  <p>Returns the empty string if {@code allNames} is empty or there is no close match.