我正在尝试获取开始日期和结束日期之间的给定日期的周数。 以下是我过去常用的代码，但它只能工作4周。
我需要它才能使它工作数周。
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java 1.7所以我无法使用 - import java.time.LocalDateTime; import java.time.temporal.ChronoUnit;
我怎么能实现，请帮助我。
答案 0 :(得分：0)
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;
}
修改
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：注意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到2016-5-6。这只有一个星期。
答案 1 :(得分：0)
不要将java.sql.Timestamp用于业务逻辑。该类仅用于与数据库交换数据。甚至这个目的现在也被java.time类所取代。对于Java 7，请使用下面的项目符号中列出的java.time的后端。
java.util.Date，java.util.Calendar和java.text.SimpleTextFormat等棘手的旧日期时间类现在是legacy，取代了java.time类。
DayOfWeek 指定您认为是一周开始的星期几。使用DayOfWeek枚举对象。顺便提一下，标准ISO 8601 week定义从星期一开始。
DayOfWeek dowStart = DayOfWeek.MONDAY ;
LocalDate LocalDate类表示没有时间且没有时区的仅限日期的值。
指定开始/停止日期。
LocalDate start = LocalDate.parse( 2016 , 4 , 9 ) ;
LocalDate stop = LocalDate.parse( 2016 , 6 , 28 ) ;
LocalDate first = start.with( TemporalAdjusters.previousOrSame( dowStart ) ) ;
List<LocalDate> dates = new ArrayList<>() ;
LocalDate ld = first ; // Initialize for loop.
while( ld.isBefore( stop ) ) { // While the local date is before the stopping point.
dates.add( ld ) ;
// Prepare for next loop.
ld = ld.plusWeeks( 1 ) ;
}
现在以您选择的任何方式报告您的工作日开始日期。
int i = 0 ; // Initialize for loop.
for( LocalDate ld : dates ) {
i ++ ;
String output = "Week # " + i + ":" + ld + " - " + ld.plusDays( 6 ) ;
…
}
java.time框架内置于Java 8及更高版本中。这些类取代了麻烦的旧legacy日期时间类，例如java.util.Date，Calendar和＆amp; SimpleDateFormat
现在位于Joda-Time的maintenance mode项目建议迁移到java.time类。
要了解详情，请参阅Oracle Tutorial。并搜索Stack Overflow以获取许多示例和解释。规范是JSR 310。
从哪里获取java.time类？
ThreeTen-Extra项目使用其他类扩展java.time。该项目是未来可能添加到java.time的试验场。您可以在此处找到一些有用的课程，例如Interval，YearWeek，YearQuarter和more。