int colonIndex = hostPortString.indexOf(':');
    int closeBracketIndex = hostPortString.lastIndexOf(']');
    checkArgument(
        colonIndex > -1 && closeBracketIndex > colonIndex,
        "Invalid bracketed host/port: %s",
        hostPortString);

    String host = hostPortString.substring(1, closeBracketIndex);
    if (closeBracketIndex + 1 == hostPortString.length()) {
      return new String[] {host, ""};