怎么求两个Calendar对象相隔有多少天？

Question

这东西正好我也做过，不过方法比较土呵呵，我用了java核心编程那本书附带的一个类
corejava.Day,  很容易使用。 
先new 两个Day出来,然后第一个Day不断前进,Day.advance(1),碰到周六周末略去，一直比较到后一个Day为止(*&^

Answer 1

找不到什么好的方法
public int getDays(Date sd,Date ed){
    return (ed.getTime() - sd.getTime()) / (24*3600*1000)
}  这样要是再想去掉节假日就麻烦了

Answer 2

c1,c2之间有多少天:
public int dayDiff(GregorianCalendar c1, GregorianCalendar c2){
if((c1.get(Calendar.YEAR)==c2.get(Calendar.YEAR)) && 
   (c1.get(Calendar.DAY_OF_YEAR)==c2.get(Calendar.DAY_OF_YEAR)))
   return 0;
else 
   return (int)
Math.ceil((Math.abs(c1.getTimeInMillis()-c2.getTimeInMillis()))/(1000*24*3600.0));
}

Answer 3

Date date1 = c1.getTime();
Date date2 = c2.getTime();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String str1 = sdf.format(date1);
String str2 = sdf.format(date2);
date1 = sdf.parse(str1);
date2 = sdf.parse(str2);
int nDays = Math.abs((date2.getTime - date1.getTime)/(24 * 60 * 60 *1000));

Answer 4

int getWeekDay(Calendar)//得到该日期是星期几
boolean isWeekEnd(Calendar)
boolean isHoliday(Calendar)
int getWeekEndCount(Calendar,Calendar)
int getHolidayCount(Calendar,Calendar)
int getValidDayCount(Calendar,Calendar)

Answer 5

Calendar c0=Calendar.getInstance();
       c0.set(2003,11,14);
       Calendar c1=Calendar.getInstance();
       c1.set(2002,11,14);
//-----求两个Calendar: c0,c1相差的天数
       Date ddd1=c0.getTime();
       Date ddd2=c1.getTime();
       long d=ddd1.getTime()-ddd2.getTime();
       d=d/3600/24/1000;     // 毫秒--->天数

Answer 6

must determine if c1 and c2 are the same day. 
c1:2003-11-20-18:23:23
c2:2003-11-20-00:01:00 
c1-c2=0c1:2003-11-20-18:23:23
c2:2003-11-21-00:01:00
c2-c1=1Test if your algo is right

Answer 7

int workDayDiff(c1,c2){
if(c1.after(c2))
   return  workDayDiff(c2,c1);
int offset=(dayDiff(c1,c2) % 7)*5;int dw2=c2.get(Calendar.DAY_OF_WEEK);
int dw1=c1.get(Calendar.DAY_OF_WEEK);
....

Answer 8

算法：
  首先计算出时间差，以天为单位；整除7得到工作周；关键是剩下那几天的计算，具体算法见测试程序。测试用源代码如下：
import java.util.Calendar;public class Test {
public static void main(String args[]){
Calendar c1 = Calendar.getInstance();
Calendar c2 = Calendar.getInstance();
long millisPerDay = 1000 * 60 * 60 * 24;
long diff = millisPerDay * 8;
c1.setTimeInMillis(System.currentTimeMillis() - diff );
c2.setTimeInMillis(System.currentTimeMillis());

long diffInMilliseconds = c2.getTimeInMillis() - c1.getTimeInMillis();
long diffInDays = diffInMilliseconds / (1000 * 60 * 60 * 24) ;
long diffInWeeks = diffInDays / 7;
long workDays = diffInDays / 7 * 5;

         /* 剩下几天的算法 */
long rem = diffInDays % 7;
int curDayInWeek = c2.get(Calendar.DAY_OF_WEEK);
if (rem <= curDayInWeek - Calendar.SUNDAY) 
workDays += rem;
else if (rem <= curDayInWeek - Calendar.SUNDAY + 2)
workDays += curDayInWeek - Calendar.SUNDAY;
else 
workDays += rem - 2;

System.out.println("days:\t" + diffInDays);
System.out.println("workdays:\t" + workDays);
}
}