code: static String removeKeyword(String clause, String keyword) {
      keyword = keyword + " ";
      if (clause.regionMatches(true, 0, keyword, 0, keyword.length())) {
        return clause.substring(keyword.length());
      }
      return clause;
    }
docs: Removes the {@code keyword} from the {@code clause} if present. Will
  remove {@code keyword + " "}.
  @param clause the clause to remove from
  @param keyword the keyword to remove
  @return a new string with the keyword + " " removed