code: public static Date getCanonicalTime(Date date)
     {
        if (date != null)
        {
           Calendar cal = popCalendar(date);
           cal.set(Calendar.DAY_OF_YEAR, 1);
           cal.set(Calendar.YEAR, 1);
           cal.set(Calendar.MILLISECOND, 0);
           date = cal.getTime();
           pushCalendar(cal);
        }
        return (date);
     }
docs: This method resets the date part of a date time value to
  a standard date (1/1/1). This is used to allow times to
  be compared and manipulated.
  
  @param date date time value
  @return date time with date set to a standard value