toString method

@override String toString()

Dotted quad for IPv4; RFC 5952 form for IPv6.

Implementation

@override
String toString() {
  if (isIPv4) return _bytes.join('.');
  final List<int> groups = <int>[
    for (int i = 0; i < 16; i += 2) (_bytes[i] << 8) | _bytes[i + 1],
  ];
  // The longest run of two or more zero groups, the first on a tie.
  int bestStart = -1;
  int bestLength = 1;
  for (int i = 0; i < 8;) {
    if (groups[i] != 0) {
      i++;
      continue;
    }
    int j = i;
    while (j < 8 && groups[j] == 0) {
      j++;
    }
    if (j - i > bestLength) {
      bestStart = i;
      bestLength = j - i;
    }
    i = j;
  }
  String hex(Iterable<int> part) =>
      part.map((int g) => g.toRadixString(16)).join(':');
  if (bestStart < 0) return hex(groups);
  return '${hex(groups.take(bestStart))}::'
      '${hex(groups.skip(bestStart + bestLength))}';
}