返回相差天数

 public static long getDistDates(Date startDate,Date endDate){    
        long totalDate = 0;    
        Calendar calendar = Calendar.getInstance();    
        calendar.setTime(startDate);    
        long timestart = calendar.getTimeInMillis();    
        calendar.setTime(endDate);    
        long timeend = calendar.getTimeInMillis();    
        totalDate = Math.abs((timeend - timestart))/(1000*60*60*24);    
        return totalDate;    
 }