SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date birth = sdf.parse("2000-01-01");
Date now = new Date(System.currentTimeMillis());
Calendar c = Calendar.getInstance();
c.setTimeInMillis(now.getTime() - birth.getTime());
int y = c.get(Calendar.YEAR)-1970;
int m = c.get(Calendar.MONTH);
int d = c.get(Calendar.DAY_OF_MONTH)-1;