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how to get a list of dates between two dates in java

I want a list of dates between start date and end date.

The result should be a list of all dates including the start and 开发者_运维知识库end date.


java.time Package

If you are using Java 8, there is a much cleaner approach. The new java.time package in Java 8 incorporates the features of the Joda-Time API.

Your requirement can be solved using the below code:

String s = "2014-05-01";
String e = "2014-05-10";
LocalDate start = LocalDate.parse(s);
LocalDate end = LocalDate.parse(e);
List<LocalDate> totalDates = new ArrayList<>();
while (!start.isAfter(end)) {
    totalDates.add(start);
    start = start.plusDays(1);
}


Back in 2010, I suggested to use Joda-Time for that.

Note that Joda-Time is now in maintenance mode. Since 1.8 (2014), you should use java.time.

Add one day at a time until reaching the end date:

int days = Days.daysBetween(startDate, endDate).getDays();
List<LocalDate> dates = new ArrayList<LocalDate>(days);  // Set initial capacity to `days`.
for (int i=0; i < days; i++) {
    LocalDate d = startDate.withFieldAdded(DurationFieldType.days(), i);
    dates.add(d);
}

It wouldn't be too hard to implement your own iterator to do this as well, that would be even nicer.


Get the number of days between dates, inclusive.

public static List<Date> getDaysBetweenDates(Date startdate, Date enddate)
{
    List<Date> dates = new ArrayList<Date>();
    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;
}


Streams

Edit: Joda-Time is now deprecated, changed the answer to use Java 8 instead.

Here is the Java 8 way, using streams.

List<LocalDate> daysRange = Stream.iterate(startDate, date -> date.plusDays(1)).limit(numOfDays).collect(Collectors.toList());


please find the below code.

List<Date> dates = new ArrayList<Date>();

String str_date ="27/08/2010";
String end_date ="02/09/2010";

DateFormat formatter ; 

formatter = new SimpleDateFormat("dd/MM/yyyy");
Date  startDate = (Date)formatter.parse(str_date); 
Date  endDate = (Date)formatter.parse(end_date);
long interval = 24*1000 * 60 * 60; // 1 hour in millis
long endTime =endDate.getTime() ; // create your endtime here, possibly using Calendar or Date
long curTime = startDate.getTime();
while (curTime <= endTime) {
    dates.add(new Date(curTime));
    curTime += interval;
}
for(int i=0;i<dates.size();i++){
    Date lDate =(Date)dates.get(i);
    String ds = formatter.format(lDate);    
    System.out.println(" Date is ..." + ds);
}

output:

Date is ...27/08/2010
Date is ...28/08/2010
Date is ...29/08/2010
Date is ...30/08/2010
Date is ...31/08/2010
Date is ...01/09/2010
Date is ...02/09/2010


Recommending date streams

In Java 9, you can use following new method, LocalDate::datesUntil:

LocalDate start = LocalDate.of(2017, 2, 1);
LocalDate end = LocalDate.of(2017, 2, 28);

Stream<LocalDate> dates = start.datesUntil(end.plusDays(1));
List<LocalDate> list = dates.collect(Collectors.toList());

The new method datesUntil(...) works with an exclusive end date, hence the shown hack to add a day.

Once you have obtained a stream you can exploit all the features offered by java.util.stream- or java.util.function-packages. Working with streams has become so simple compared with earlier approaches based on customized for- or while-loops.


Or if you look for a stream-based solution which operates on inclusive dates by default but can also be configured otherwise then you might find the class DateInterval in my library Time4J interesting because it offers a lot of special features around date streams including a performant spliterator which is faster than in Java-9:

PlainDate start = PlainDate.of(2017,  2, 1);
PlainDate end = start.with(PlainDate.DAY_OF_MONTH.maximized());
Stream<PlainDate> stream = DateInterval.streamDaily(start, end);

Or even simpler in case of full months:

Stream<PlainDate> februaryDates = CalendarMonth.of(2017, 2).streamDaily();
List<LocalDate> list = 
    februaryDates.map(PlainDate::toTemporalAccessor).collect(Collectors.toList());


With java 8

public Stream<LocalDate> getDaysBetween(LocalDate startDate, LocalDate endDate) {
    return IntStream.range(0, (int) DAYS.between(startDate, endDate)).mapToObj(startDate::plusDays);
}


Something like this should definitely work:

private List<Date> getListOfDaysBetweenTwoDates(Date startDate, Date endDate) {
    List<Date> result = new ArrayList<Date>();
    Calendar start = Calendar.getInstance();
    start.setTime(startDate);
    Calendar end = Calendar.getInstance();
    end.setTime(endDate);
    end.add(Calendar.DAY_OF_YEAR, 1); //Add 1 day to endDate to make sure endDate is included into the final list
    while (start.before(end)) {
        result.add(start.getTime());
        start.add(Calendar.DAY_OF_YEAR, 1);
    }
    return result;
}


With Lamma it looks like this in Java:

    for (Date d: Dates.from(2014, 6, 29).to(2014, 7, 1).build()) {
        System.out.println(d);
    }

and the output is:

    Date(2014,6,29)
    Date(2014,6,30)
    Date(2014,7,1)


 public static List<Date> getDaysBetweenDates(Date startDate, Date endDate){
        ArrayList<Date> dates = new ArrayList<Date>();
        Calendar cal1 = Calendar.getInstance();
        cal1.setTime(startDate);

        Calendar cal2 = Calendar.getInstance();
        cal2.setTime(endDate);

        while(cal1.before(cal2) || cal1.equals(cal2))
        {
            dates.add(cal1.getTime());
            cal1.add(Calendar.DATE, 1);
        }
        return dates;
    }


One solution would be to create a Calendar instance, and start a cycle, increasing it's Calendar.DATE field until it reaches the desired date. Also, on each step you should create a Date instance (with corresponding parameters), and put it to your list.

Some dirty code:

    public List<Date> getDatesBetween(final Date date1, final Date date2) {
    List<Date> dates = new ArrayList<Date>();

    Calendar calendar = new GregorianCalendar() {{
        set(Calendar.YEAR, date1.getYear());
        set(Calendar.MONTH, date1.getMonth());
        set(Calendar.DATE, date1.getDate());
    }};

    while (calendar.get(Calendar.YEAR) != date2.getYear() && calendar.get(Calendar.MONTH) != date2.getMonth() && calendar.get(Calendar.DATE) != date2.getDate()) {
        calendar.add(Calendar.DATE, 1);
        dates.add(new Date(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DATE)));
    }

    return dates;
}


You can also look at the Date.getTime() API. That gives a long to which you can add your increment. Then create a new Date.

List<Date> dates = new ArrayList<Date>();
long interval = 1000 * 60 * 60; // 1 hour in millis
long endtime = ; // create your endtime here, possibly using Calendar or Date
long curTime = startDate.getTime();
while (curTime <= endTime) {
  dates.add(new Date(curTime));
  curTime += interval;
}

and maybe apache commons has something like this in DateUtils, or perhaps they have a CalendarUtils too :)

EDIT

including the start and enddate may not be possible if your interval is not perfect :)


List<Date> dates = new ArrayList<Date>();
String str_date = "DD/MM/YYYY";
String end_date = "DD/MM/YYYY";
DateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
Date startDate = (Date)formatter.parse(str_date); 
Date endDate = (Date)formatter.parse(end_date);
long interval = 1000 * 60 * 60; // 1 hour in milliseconds
long endTime = endDate.getTime() ; // create your endtime here, possibly using Calendar or Date
long curTime = startDate.getTime();

while (curTime <= endTime) {
    dates.add(new Date(curTime));
    curTime += interval;
}
for (int i = 0; i < dates.size(); i++){
    Date lDate = (Date)dates.get(i);
    String ds = formatter.format(lDate);    
    System.out.println("Date is ..." + ds);
    //Write your code for storing dates to list
}


Like as @folone, but correct

private static List<Date> getDatesBetween(final Date date1, final Date date2) {
    List<Date> dates = new ArrayList<>();
    Calendar c1 = new GregorianCalendar();
    c1.setTime(date1);
    Calendar c2 = new GregorianCalendar();
    c2.setTime(date2);
    int a = c1.get(Calendar.DATE);
    int b = c2.get(Calendar.DATE);
    while ((c1.get(Calendar.YEAR) != c2.get(Calendar.YEAR)) || (c1.get(Calendar.MONTH) != c2.get(Calendar.MONTH)) || (c1.get(Calendar.DATE) != c2.get(Calendar.DATE))) {
        c1.add(Calendar.DATE, 1);
        dates.add(new Date(c1.getTimeInMillis()));
    }
    return dates;
}


With Joda-Time , maybe it's better:

LocalDate dateStart = new LocalDate("2012-01-15");
LocalDate dateEnd = new LocalDate("2012-05-23");
// day by day:
while(dateStart.isBefore(dateEnd)){
    System.out.println(dateStart);
    dateStart = dateStart.plusDays(1);
}

It's my solution.... very easy :)


This is simple solution for get a list of dates

import java.io.*;
import java.util.*;
import java.text.SimpleDateFormat;  
public class DateList
{

public static SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

 public static void main (String[] args) throws java.lang.Exception
 {

    Date dt = new Date();
    System.out.println(dt);

        List<Date> dates = getDates("2017-01-01",dateFormat.format(new Date()));
        //IF you don't want to reverse then remove Collections.reverse(dates);
         Collections.reverse(dates);
        System.out.println(dates.size());
    for(Date date:dates)
    {
        System.out.println(date);
    }
 }
 public static List<Date> getDates(String fromDate, String toDate)
 {
    ArrayList<Date> dates = new ArrayList<Date>();

    try {

        Calendar fromCal = Calendar.getInstance();
        fromCal.setTime(dateFormat .parse(fromDate));

        Calendar toCal = Calendar.getInstance();
        toCal.setTime(dateFormat .parse(toDate));

        while(!fromCal.after(toCal))
        {
            dates.add(fromCal.getTime());
            fromCal.add(Calendar.DATE, 1);
        }


    } catch (Exception e) {
        System.out.println(e);
    }
    return dates;
 }
}


As of Java 9, you can use the datesUntil method on LocalDate:

public List<LocalDate> getDatesBetween(
  LocalDate startDate, LocalDate endDate) {
  
    return startDate.datesUntil(endDate)
      .collect(Collectors.toList());
}


The LocalDateRange class in the ThreeTen-Extra library represents a range of dates, and can be used for this purpose:

LocalDateRange.ofClosed(startDate, endDate).stream().toList();


A tail-recursive version:

public static void datesBetweenRecursive(Date startDate, Date endDate, List<Date> dates) {
    if (startDate.before(endDate)) {
        dates.add(startDate);
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(startDate);
        calendar.add(Calendar.DATE, 1);
        datesBetweenRecursive(calendar.getTime(), endDate, dates);
    }
}


Enhancing one of the above solutions. As adding 1 day to end date sometimes adds an extra day beyond the end date.


    public static List getDaysBetweenDates(Date startdate, Date enddate)
    {
        List dates = new ArrayList();
        Calendar startDay = new GregorianCalendar();
        calendar.setTime(startdate);
        Calendar endDay = new GregorianCalendar();
        endDay.setTime(enddate);
        endDay.add(Calendar.DAY_OF_YEAR, 1);
        endDay.set(Calendar.HOUR_OF_DAY, 0);
        endDay.set(Calendar.MINUTE, 0);
        endDay.set(Calendar.SECOND, 0);
        endDay.set(Calendar.MILLISECOND, 0);

        while (calendar.getTime().before(endDay.getTime())) {
            Date result = startDay.getTime();
            dates.add(result);
            startDay.add(Calendar.DATE, 1);
        }
        return dates;
    }


Here is my method for getting dates between two dates, including / w.o. including business days. It also takes source and desired date format as parameter.

public static List<String> getAllDatesBetweenTwoDates(String stdate,String enddate,String givenformat,String resultformat,boolean onlybunessdays) throws ParseException{
        DateFormat sdf;
        DateFormat sdf1;
        List<Date> dates = new ArrayList<Date>();
        List<String> dateList = new ArrayList<String>();
          SimpleDateFormat checkformat = new SimpleDateFormat(resultformat); 
          checkformat.applyPattern("EEE");  // to get Day of week
        try{
            sdf = new SimpleDateFormat(givenformat);
            sdf1 = new SimpleDateFormat(resultformat);
            stdate=sdf1.format(sdf.parse(stdate));
            enddate=sdf1.format(sdf.parse(enddate));

            Date  startDate = (Date)sdf1.parse( stdate); 
            Date  endDate = (Date)sdf1.parse( enddate);
            long interval = 24*1000 * 60 * 60; // 1 hour in millis
            long endTime =endDate.getTime() ; // create your endtime here, possibly using Calendar or Date
            long curTime = startDate.getTime();
            while (curTime <= endTime) {
                dates.add(new Date(curTime));
                curTime += interval;
            }
            for(int i=0;i<dates.size();i++){
                Date lDate =(Date)dates.get(i);
                String ds = sdf1.format(lDate);   
                if(onlybunessdays){
                    String day= checkformat.format(lDate); 
                    if(!day.equalsIgnoreCase("Sat") && !day.equalsIgnoreCase("Sun")){
                          dateList.add(ds);
                    }
                }else{
                      dateList.add(ds);
                }

                //System.out.println(" Date is ..." + ds);

            }


        }catch(ParseException e){
            e.printStackTrace();
            throw e;
        }finally{
            sdf=null;
            sdf1=null;
        }
        return dateList;
    }

And the method call would be like :

public static void main(String aregs[]) throws Exception {
        System.out.println(getAllDatesBetweenTwoDates("2015/09/27","2015/10/05","yyyy/MM/dd","dd-MM-yyyy",false));
    }

You can find the demo code : Click Here


List<LocalDate> totalDates = new ArrayList<>();
popularDatas(startDate, endDate, totalDates);
System.out.println(totalDates);

private void popularDatas(LocalDate startDate, LocalDate endDate, List<LocalDate> datas) {
    if (!startDate.plusDays(1).isAfter(endDate)) {
        popularDatas(startDate.plusDays(1), endDate, datas);
    } 
    datas.add(startDate);
}

Recursive solution


This will add all dates between two dates and It will add current dates and then new dates will be added based on loop condition.

private void onDateSet(){
    Calendar endDate = Calendar.getInstance(),startDate = Calendar.getInstance();
    startDate.set(currentYear,currentMonthOfYear,currentDayOfMonth);
    endDate.set(inputYear,inputMonthOfYear,inputDayOfMonth);
    datesToAdd(startDate,endDate);
    }

    //call for get dates list
    private List<Date> datesToAdd(Calendar startDate,Calendar endDate){
                    List<Dates> datesLists = new List<>();
                    while (startDate.get(Calendar.YEAR) != endDate.get(Calendar.YEAR) ||   
                           startDate.get(Calendar.MONTH) != endDate.get(Calendar.MONTH) ||
                           startDate.get(Calendar.DAY_OF_MONTH) != endDate.get(Calendar.DAY_OF_MONTH)) {

                             datesList.add(new Date(startDate.get(Calendar.YEAR), startDate.get(Calendar.MONTH), startDate.get(Calendar.DATE));

                             startDate.add(Calendar.DATE, 1);//increas dates

                         }
                         return datesList;
                }
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