Method parseWeekBasedSymbol

base/src/main/java/net/time4j/Duration.java:3831–3849

(
        char c,
        String period,
        int index
    )

    }

    private static IsoDateUnit parseWeekBasedSymbol(
        char c,
        String period,
        int index
    ) throws ParseException {

        switch (c) {
            case 'Y':
                return CalendarUnit.weekBasedYears();
            case 'W':
                return WEEKS;
            case 'D':
                return DAYS;
            default:
                throw new ParseException(
                    "Symbol \'" + c + "\' not supported: " + period, index);
        }

    }

    private static <U extends ChronoUnit> ChronoUnit addParsedItem(
        ChronoUnit unit,