Method Moment

base/src/main/java/net/time4j/Moment.java:535–633

(
        long elapsedTime,
        int nanosecond,
        TimeScale scale
    )

    //~ Konstruktoren -----------------------------------------------------

    private Moment(
        long elapsedTime,
        int nanosecond,
        TimeScale scale
    ) {
        super();

        if (scale == POSIX) {
            this.posixTime = elapsedTime;
            this.fraction = nanosecond;
        } else {
            LeapSeconds ls = LeapSeconds.getInstance();

            if (ls.isEnabled()) {
                long utcTime;

                if (scale == UTC) {
                    utcTime = elapsedTime;
                } else if (scale == TAI) {
                    if (elapsedTime < 0) {
                        throw new IllegalArgumentException(
                            "TAI not supported before 1958-01-01: " + elapsedTime);
                    } else if (elapsedTime < UTC_TAI_DELTA) {
                        long tv = Math.addExact(elapsedTime, 32 - UTC_TAI_DELTA);
                        nanosecond = Math.addExact(nanosecond, 184_000_000);
                        if (nanosecond >= MRD) {
                            tv = Math.incrementExact(tv);
                            nanosecond = Math.subtractExact(nanosecond, MRD);
                        }
                        double tt = tv + (nanosecond / (MRD * 1.0));
                        PlainDate date = // approximation
                            PlainDate.of(Math.floorDiv((long) (tt - 42.184), 86400), EpochDays.UTC);
                        double utValue = tt - TimeScale.deltaT(date);
                        utcTime = (long) Math.floor(utValue);
                        nanosecond = toNanos(utValue, utcTime);
                    } else {
                        utcTime = Math.subtractExact(elapsedTime, UTC_TAI_DELTA + 10);
                    }
                } else if (scale == GPS) {
                    utcTime = Math.addExact(elapsedTime, UTC_GPS_DELTA);
                    if (utcTime < UTC_GPS_DELTA) {
                        throw new IllegalArgumentException(
                            "GPS not supported before 1980-01-06: " + elapsedTime);
                    }
                } else if (scale == TT) {
                    if ((elapsedTime < 42L) || ((elapsedTime == 42L) && (nanosecond < 184_000_000))) {
                        double tt = ((double) elapsedTime) + (nanosecond / (MRD * 1.0));
                        PlainDate date = // approximation
                            PlainDate.of(Math.floorDiv((long) (tt - 42.184), 86400), EpochDays.UTC);
                        double utValue = tt - TimeScale.deltaT(date);
                        utcTime = (long) Math.floor(utValue);
                        nanosecond = toNanos(utValue, utcTime);
                    } else {
                        elapsedTime = Math.subtractExact(elapsedTime, 42);
                        nanosecond = Math.subtractExact(nanosecond, 184_000_000);
                        if (nanosecond < 0) {
                            elapsedTime = Math.decrementExact(elapsedTime);
                            nanosecond = Math.addExact(nanosecond, MRD);