java - 通过在java中传递开始和结束日期获取给定日期的周数

Question

我正在尝试获取给定日期在开始日期和结束日期之间的周数。下面是我曾经得到的代码，但它只能工作 4 周。

我需要它来让它工作任意几周。

public static int getWeekNO( Timestamp startTime,Timestamp endTime , Timestamp dateTime) throws RuntimeException {

        String formatted = null;
        Timestamp currentTimestamp;
        int weekNumber = 0;

        logger.debug("startTime"+startTime);
        logger.debug("endTime"+endTime);
        logger.debug("dateTime"+dateTime);
        try {
            String formatDateFirst =  "";
            String formatDateSecond = "";
            String formatDateThird = "";
            String formatDateFourth = "";
            String givenDateString = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(dateTime);
            String startDateString = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(startTime);
            String endDateString = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(endTime);
            logger.debug("givenDateString"+givenDateString);
            logger.debug("startDateString"+startDateString);
            logger.debug("endDateString"+endDateString);


            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

            Calendar c = Calendar.getInstance();
            Date givenDate = sdf.parse(givenDateString);
            Date startDate = sdf.parse(startDateString);
            Date endDate = sdf.parse(endDateString);

            logger.debug("givenDate"+givenDate);
            logger.debug("startDate"+startDate);
            logger.debug("endDate"+endDate);

            c.setTime(sdf.parse(startDateString));

            c.add(Calendar.DAY_OF_MONTH, 6); // number of days to add
            formatDateFirst = sdf.format(c.getTime());
            Date firstWeekDate = (Date) sdf.parse(formatDateFirst);
            logger.debug("endDate"+firstWeekDate);

            c.add(Calendar.DAY_OF_MONTH, 7); // number of days to add
            formatDateSecond = sdf.format(c.getTime());
            Date secondWeekDate = (Date) sdf.parse(formatDateSecond);
            logger.debug("endDate"+secondWeekDate);

            c.add(Calendar.DAY_OF_MONTH, 7); // number of days to add
            formatDateThird = sdf.format(c.getTime());
            Date thirdWeekDate = (Date) sdf.parse(formatDateThird);
            logger.debug("endDate"+thirdWeekDate);

            c.add(Calendar.DAY_OF_MONTH, 7); // number of days to add
            formatDateFourth = sdf.format(c.getTime());
            Date fourthWeekDate = (Date) sdf.parse(formatDateFourth);
            logger.debug("endDate"+fourthWeekDate);


            if (givenDate.compareTo(firstWeekDate) <= 0) {
                weekNumber = 1;
            } else if (givenDate.compareTo(secondWeekDate) <= 0
                    && givenDate.compareTo(firstWeekDate) > 0) {
                weekNumber = 2;
                } else if (givenDate.compareTo(thirdWeekDate) <= 0
                    && givenDate.compareTo(secondWeekDate) > 0) {
                    weekNumber = 3;
            }else if (givenDate.compareTo(fourthWeekDate) <= 0
                    && givenDate.compareTo(thirdWeekDate) > 0) {
                    weekNumber = 4;
            }else{
                logger.debug("Not a Valid Date");
            }

        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
        return weekNumber;
    } 

示例:

  start Timestamp: 09/04/2016 00:00:00,End Timestamp: 28/06/2016 00:00:00. Given Timestamp : 15/05/2016 00:00:00

so here:week 1:09/04/2016 - 15/04/2016
        week 2:16/04/2016 - 22/04/2016
        week 3:23/04/2016 - 29/04/2016
        week 4:30/04/2016 - 06/05/2016
        week 5:07/05/2016 - 13/05/2016
        week 6:14/05/2016 - 20/05/2016 -- my given timestamp falls here
        week 7:21/05/2016 - 27/05/2016
        week 8:28/05/2016 - 03/06/2016

so now my output for week no should be week:6 

这里我使用的是java 1.7，所以我无法使用--import java.time.LocalDateTime;导入 java.time.temporal.ChronoUnit;

我怎样才能实现，请帮助我。

Answer 1

    public static int getWeekNO(Timestamp startTime, Timestamp endTime, Timestamp dateTime) {
      if (dateTime.compareTo(startTime) < 0 || dateTime.compareTo(endTime) > 0) {
        System.out.println("Not a Valid Date");
        return -1;
      }
      return (int) ((dateTime.getTime() - startTime.getTime() - 1) / (1000L * 3600 * 24 * 7)) + 1;
    }

<小时/>

编辑:

根据要求，更新了答案，

public static int getWeekNO(Timestamp startTime, Timestamp endTime, Timestamp dateTime) {
  if (dateTime.compareTo(startTime) < 0 || dateTime.compareTo(endTime) > 0) {
    System.out.println("Not a Valid Date");
    return -1;
  }
  int dayDiff = (int) ((dateTime.getTime() - startTime.getTime()) / (1000L * 3600 * 24)) + 1;
  int week = dayDiff / 7;
  return dayDiff % 7 == 0 ? week : week + 1;
}

注意:要小心Date/Timestamp的构造函数，

  Timestamp startTime = new Timestamp(2016, 5, 30, 0, 0, 0, 0);
  Timestamp dateTime = new Timestamp(2016, 6, 6, 0, 0, 0, 0);

这个构造函数月份从 0 开始。所以上面的代码是比较 2016-4-30 和 2016-5-6。只有一周时间。