while (i + 4 <= utf16Length) {
          char c0 = input.charAt(i);
          char c1 = input.charAt(i + 1);
          char c2 = input.charAt(i + 2);
          char c3 = input.charAt(i + 3);
          if (c0 < 0x80 && c1 < 0x80 && c2 < 0x80 && c3 < 0x80) {
            update(4, c0 | (c1 << 8) | (c2 << 16) | (c3 << 24));
            i += 4;
          } else {
            break;
          }
        }

            return idx < expression.length() ? expression.charAt(idx) : EOF;
        }

        public int skipChar() {
            return idx < expression.length() ? expression.charAt(idx++) : EOF;
        }

        public String nextToken(char delimiter) {
            int start = idx;

            while (idx < expression.length() && delimiter != expression.charAt(idx)) {
                idx++;
            }

                    boolean active = true;
                    if (!selector.isEmpty()) {
                        if (selector.charAt(0) == '-' || selector.charAt(0) == '!') {
                            active = false;
                            selector = selector.substring(1);
                        } else if (token.charAt(0) == '+') {
                            selector = selector.substring(1);
                        }
                    }

    if (chars instanceof String) {
      return toLowerCase((String) chars);
    }
    char[] newChars = new char[chars.length()];
    for (int i = 0; i < newChars.length; i++) {
      newChars[i] = toLowerCase(chars.charAt(i));
    }
    return String.valueOf(newChars);
  }

  /**
   * If the argument is an {@linkplain #isUpperCase(char) uppercase ASCII character}, returns the

                retValue = retValue.substring(2);

                if (retValue.length() >= 2 && (retValue.charAt(1) == '|' || retValue.charAt(1) == ':')) {
                    // special case: if there is a windows drive letter, then keep the original return value
                    retValue = retValue.charAt(0) + ":" + retValue.substring(2);
                } else {
                    // Now we expect the host

        l1 = path1.length() - p1;
        l2 = path2.length() - p2;

        // anything with dots voids comparison
        if ( l1 > 1 && path1.charAt(p1 + 1) == '.' )
            return true;
        if ( l2 > 1 && path2.charAt(p2 + 1) == '.' )
            return true;

        return l1 == l2 && path1.regionMatches(true, p1, path2, p2, l1);
    }


    /**
     * 

    private static final String COMMENT_CHARS = "#!";

    /** The list of possible key/value separators */
    private static final char[] SEPARATORS = new char[] {'=', ':'};

    /** The white space characters used as key/value separators. */
    private static final char[] WHITE_SPACE = new char[] {' ', '\t', '\f'};

    /**
     * Unless standard java props, use UTF-8
     */

        }
      }
    }
    if (ipString.charAt(0) == IPV6_DELIMITER && ipString.charAt(1) != IPV6_DELIMITER) {
      return null; // ^: requires ^::
    }
    if (ipString.charAt(ipString.length() - 1) == IPV6_DELIMITER
        && ipString.charAt(ipString.length() - 2) != IPV6_DELIMITER) {
      return null; // :$ requires ::$
    }

        if (isEmpty(name)) {
            return name;
        }
        final char[] chars = name.toCharArray();
        if (chars.length >= 2 && Character.isUpperCase(chars[0]) && Character.isUpperCase(chars[1])) {
            return name;
        }
        chars[0] = Character.toLowerCase(chars[0]);
        return new String(chars);
    }

    /**

                continue;
            }

            char ch = s.charAt(pos);
            pos++;
            if (ch == '\\') {
                sb.append(ch);
                if (pos >= end) {
                    break; // ERROR, or let it go?
                }
                ch = s.charAt(pos);
                pos++;
            }

            sb.append(ch);
        }