code: public static long dateToFileTime(final Date date) {
          checkNotNull("date", date);
          final long msSince19700101 = date.getTime();
          final long msSince16010101 = msSince19700101 + EPOCH_DIFF;
          return msSince16010101 * (1000 * 10);
      }
docs: Converts Date into a Windows FILETIME. The Windows FILETIME structure holds a date and time associated with a file. The structure
  identifies a 64-bit integer specifying the number of 100-nanosecond intervals which have passed since January 1, 1601. This code is
  copied from the <code>org.apache.poi.hpsf.Util</code> class.
  
  @param date
  The date to be converted - Cannot be <code>null</code>.
  @return The file time