code: public static Timestamp fromMillis(long epochMilli) {
      long secs = floorDiv(epochMilli, MILLIS_PER_SECOND);
      int mos = (int) floorMod(epochMilli, MILLIS_PER_SECOND);
      return create(secs, (int) (mos * NANOS_PER_MILLI)); // Safe int * NANOS_PER_MILLI
    }
docs: Creates a new timestamp from the given milliseconds.
  
  @param epochMilli the timestamp represented in milliseconds since epoch.
  @return new {@code Timestamp} with specified fields.
  @throws IllegalArgumentException if the number of milliseconds is out of the range that can be
  represented by {@code Timestamp}.
  @since 0.5