class TimeDatumStream extends MBStream<Datum> {

    public List<Datum> drainDuration(long duration) {
        int i = 0;
        long startTime = getDatumTime(i);
        while (i < output.size() && getDatumTime(i) - startTime < duration) {
            i ++;
        }
        return drain(i);
    }

    public  TimeDatumStream(int timeColumn);
    public  TimeDatumStream(List<Datum> data, int timeColumn);

}