@Nullable
  private static Pattern buildPattern(Collection<String> stringSet) {
    final StringBuilder sb = new StringBuilder();
    for (String s : stringSet) {
      if (!InjectorUtils.isRegexp(s)) continue;
      if (sb.length() > 0) sb.append('|');
      sb.append("(?:").append(s).append(")");
    }
    return sb.length() == 0 ? null : Pattern.compile(sb.toString());
  }
@Nullable
  private static Pattern buildPattern(Collection<String> stringSet)