*/
  @Override
  public String escape(String string) {
    checkNotNull(string);
    int end = string.length();
    int index = nextEscapeIndex(string, 0, end);
    return index == end ? string : escapeSlow(string, index);
  }

  /**
   * Scans a sub-sequence of characters from a given {@link CharSequence}, returning the index of
   * the next character that requires escaping.
   *