this.ignoreCase = settings.getAsBoolean("ignore_case", false);
        this.removeTrailing = settings.getAsBoolean("remove_trailing", true);
        this.stopWords =
                Analysis.parseWords(env, settings, "stopwords", JapaneseAnalyzer.getDefaultStopSet(), NAMED_STOP_WORDS, ignoreCase);
    }

    @Override
    public TokenStream create(TokenStream tokenStream) {
        if (removeTrailing) {

	port, err := strconv.ParseUint(strings.TrimSpace(portStr), 10, 16)
	if err != nil {
		return 0, fmt.Errorf("failed parsing port %q: %v", portStr, err)
	}
	return uint16(port), nil
}

func parsePorts(portsString string) ([]int, error) {
	portsString = strings.TrimSpace(portsString)
	ports := make([]int, 0)
	if len(portsString) > 0 {
		for _, portStr := range splitPorts(portsString) {