Learn to get all the dates between the two given dates. We will see the solutions in Java 7, Java 8, and Java 9.
1. LocalDate.datesUntil() (since Java 9)
LocalDate‘s datesUntil() method returns a sequential ordered stream of all dates between two given dates. The returned stream starts from startDate
(inclusive) and goes to endDate
(exclusive) by an incremental step of 1 day.
LocalDate startDate = LocalDate.now();
LocalDate endDate = startDate.plusMonths(2);
List<LocalDate> listOfDates = startDate.datesUntil(endDate)
.collect(Collectors.toList());
System.out.println(listOfDates.size()); // 61
2. Using Stream API
To get all dates, create a stream of dates adding 1 to startDate and so on, until the endDate.
LocalDate startDate = LocalDate.now();
LocalDate endDate = startDate.plusMonths(2);
long numOfDays = ChronoUnit.DAYS.between(startDate, endDate);
List<LocalDate> listOfDates = Stream.iterate(startDate, date -> date.plusDays(1))
.limit(numOfDays)
.collect(Collectors.toList());
System.out.println(listOfDates.size()); // 61
The same stream of dates can be obtained in multiple ways. For example, LongStream
is one of those ways.
LocalDate startDate = LocalDate.now();
LocalDate endDate = startDate.plusMonths(2);
long numOfDays = ChronoUnit.DAYS.between(startDate, endDate);
List<LocalDate> listOfDates = LongStream.range(0, numOfDays)
.mapToObj(startDate::plusDays)
.collect(Collectors.toList());
System.out.println(listOfDates.size()); // 61
3. Creating All Dates in Loop – Java 7
To get all dates from startDate
to endDate
in Java 7, we must write our own custom logic as there is very limited API support in JDK. Or else, consider using 3rd party libraries e.g. Joda-time.
Date todaysDate = new Date();
Date anotherDate = new Date(todaysDate.getTime() + 61*24*60*60*1000l);
List<Date> listOfDates3 = getDaysBetweenDates(todaysDate, anotherDate);
System.out.println(listOfDates3.size()); //61
public static List<Date> getDaysBetweenDates(Date startdate, Date enddate)
{
List<Date> dates = new ArrayList<>();
Calendar calendar = new GregorianCalendar();
calendar.setTime(startdate);
while (calendar.getTime().before(enddate))
{
Date result = calendar.getTime();
dates.add(result);
calendar.add(Calendar.DATE, 1);
}
return dates;
}
Happy Learning !!