code: public void setDayExcluded (final int day, final boolean exclude)
    {
      if ((day < 1) || (day > MAX_DAYS_IN_MONTH))
      {
        throw new IllegalArgumentException ("The day parameter must be in the range of 1 to " + MAX_DAYS_IN_MONTH);
      }
  
      m_aExcludeDays[day - 1] = exclude;
      m_aExcludeAll = areAllDaysExcluded ();
    }
docs: <p>
  Redefine a certain day of the month to be excluded (true) or included
  (false).
  </p>
  
  @param day
  The day of the month (from 1 to 31) to set.