Method ofWeekdate

base/src/main/java/net/time4j/PlainDate.java:2185–2241

(
        int yearOfWeekdate,
        int weekOfYear,
        Weekday dayOfWeek,
        boolean validating
    )

    }

    private static PlainDate ofWeekdate(
        int yearOfWeekdate,
        int weekOfYear,
        Weekday dayOfWeek,
        boolean validating
    ) {

        if ((weekOfYear < 1) || (weekOfYear > 53)) {
            if (validating) {
                throw new IllegalArgumentException(woyFailed(weekOfYear));
            } else {
                return null;
            }
        }

        if (
            validating
            && ((yearOfWeekdate < MIN_YEAR) || (yearOfWeekdate > MAX_YEAR))
        ) {
            throw new IllegalArgumentException(yowFailed(yearOfWeekdate));
        }

        Weekday wdNewYear =
            Weekday.valueOf(GregorianMath.getDayOfWeek(yearOfWeekdate, 1, 1));
        int dow = wdNewYear.getValue();
        int doy = (
            ((dow <= 4) ? 2 - dow : 9 - dow)
            + (weekOfYear - 1) * 7
            + dayOfWeek.getValue() - 1
        );
        int y = yearOfWeekdate;

        if (doy <= 0) {
            y--;
            doy += (GregorianMath.isLeapYear(y) ? 366 : 365);
        } else {
            int yearlen =
                (GregorianMath.isLeapYear(y) ? 366 : 365);
            if (doy > yearlen) {
                doy -= yearlen;
                y++;
            }
        }

        PlainDate result = PlainDate.ofYearDay(y, doy, dayOfWeek);

        if ((weekOfYear == 53) && (result.getWeekOfYear() != 53)) {
            if (validating) {
                throw new IllegalArgumentException(woyFailed(weekOfYear));
            } else {
                return null;
            }
        }

        return result;

    }