????1????????
????????????????
?????????????????????????
????2?????????
????????1??
???????Calendar??????????????????????????￡?
???????????????????????2012???????2015???
????????????????????????????????
/**
* date2??date1???????
* @param date1
* @param date2
* @return
*/
public static int differentDays(Date date1??Date date2)
{
Calendar cal1 = Calendar.getInstance();
cal1.setTime(date1);
Calendar cal2 = Calendar.getInstance();
cal2.setTime(date2);
int day1= cal1.get(Calendar.DAY_OF_YEAR);
int day2 = cal2.get(Calendar.DAY_OF_YEAR);
int year1 = cal1.get(Calendar.YEAR);
int year2 = cal2.get(Calendar.YEAR);
if(year1 != year2)   //????
{
int timeDistance = 0 ;
for(int i = year1 ; i < year2 ; i ++)
{
if(i%4==0 && i%100!=0 || i%400==0)    //????
{
timeDistance += 366;
}
else    //????????
{
timeDistance += 365;
}
}
return timeDistance + (day2-day1) ;
}
else    //?????
{
System.out.println("?ж?day2 - day1 : " + (day2-day1));
return day2-day1;
}
}
????????2??
????????????????????????????????????????????????????????????????????????????????
????/**
????* ??????????????ж???????????
????* @param date1
????* @param date2
????* @return
????*/
????public static int differentDaysByMillisecond(Date date1??Date date2)
????{
????int days = (int) ((date2.getTime() - date1.getTime()) / (1000*3600*24));
????return days;
????}
?????????
public static void main(String[] args)
{
String dateStr = "2008-1-1 1:21:28";
String dateStr2 = "2010-1-2 1:21:28";
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat format2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try
{
Date date2 = format.parse(dateStr2);
Date date = format.parse(dateStr);
System.out.println("???????????" + differentDays(date??date2));
System.out.println("???????????" + differentDaysByMillisecond(date??date2));
} catch (ParseException e) {
e.printStackTrace();
}
}
?????????
???????????????732
???????????????732
??????????????????
????????????????????????????б?????????????????????????о??????????????????????????????????????????????????????
?????????????????????????????????????????????????????????????????????????С????????????????23??С??????????????????????????????
????2015-1-1 21:21:28
????2015-1-2 1:21:28
???????????
public static void main(String[] args)
{
String dateStr = "2015-1-1 21:21:28";
String dateStr2 = "2015-1-2 1:21:28";
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat format2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try
{
Date date2 = format.parse(dateStr2);
Date date = format.parse(dateStr);
System.out.println("???????????" + differentDays(date??date2));
System.out.println("???????????" + differentDaysByMillisecond(date??date2));
} catch (ParseException e) {
e.printStackTrace();
}
}
?????????
???????????????1
???????????????0
??????????????????????????????24С???????2?????????????1????????????????????ж???????????