code: @Deprecated
      public static <T extends Calendar> T roll(final T calendar, final long amount, final TimeUnit unit) {
          N.checkArgNotNull(calendar, "calendar");
  
          return createCalendar(calendar, calendar.getTimeInMillis() + unit.toMillis(amount));
      }
docs: Adds or subtracts the specified amount of time to the given time unit,
  based on the calendar's rules. For example, to subtract 5 days from the
  current time of the calendar, you can achieve it by calling:
  <p>
  <code>N.roll(c, -5, TimeUnit.DAYS)</code>.
  
  @param calendar
  @param amount
  @param unit
  @return a new instance of Calendar with the specified amount rolled.
  @deprecated replaced by {@code addYears/addMonths/addWeeks/...}