java中日期的计算问题

计算日期加减几天后的日期

public static String newDate(Date beginDate, int data) throws ParseException{SimpleDateFormat dft = new SimpleDateFormat("yyyy-MM-dd");Calendar date = Calendar.getInstance();date.setTime(beginDate);date.set(Calendar.DATE, date.get(Calendar.DATE) + data);Date endDate = dft.parse(dft.format(date.getTime()));return dft.format(endDate);}

计算两个日期相差的天数

public static long getQuot(String time1, String time2){  long quot = 0;  SimpleDateFormat ft = new SimpleDateFormat("yyyy-MM-dd");  try {   Date date1 = ft.parse( time1 );   Date date2 = ft.parse( time2 );   quot = date1.getTime() - date2.getTime();   quot = quot / 1000 / 60 / 60 / 24;  } catch (ParseException e) {   e.printStackTrace();  }  return quot; }