Start and end date of a current month

Question

I need the start date and the end date of the current month in Java. When the JSP page is loaded with the current month it should automatically calculate the start and end date of that month. It should be irrespective of the year and month. That is some month has 31 days or 30 days or 28 days. This should satisfy for a leap year too. Can you help me out with that?

For example if I select month May in a list box I need starting date that is 1 and end date that is 31.

Answer 1

There you go:

public Pair<Date, Date> getDateRange() {
    Date begining, end;

    {
        Calendar calendar = getCalendarForNow();
        calendar.set(Calendar.DAY_OF_MONTH,
                calendar.getActualMinimum(Calendar.DAY_OF_MONTH));
        setTimeToBeginningOfDay(calendar);
        begining = calendar.getTime();
    }

    {
        Calendar calendar = getCalendarForNow();
        calendar.set(Calendar.DAY_OF_MONTH,
                calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
        setTimeToEndofDay(calendar);
        end = calendar.getTime();
    }

    return Pair.of(begining, end);
}

private static Calendar getCalendarForNow() {
    Calendar calendar = GregorianCalendar.getInstance();
    calendar.setTime(new Date());
    return calendar;
}

private static void setTimeToBeginningOfDay(Calendar calendar) {
    calendar.set(Calendar.HOUR_OF_DAY, 0);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    calendar.set(Calendar.MILLISECOND, 0);
}

private static void setTimeToEndofDay(Calendar calendar) {
    calendar.set(Calendar.HOUR_OF_DAY, 23);
    calendar.set(Calendar.MINUTE, 59);
    calendar.set(Calendar.SECOND, 59);
    calendar.set(Calendar.MILLISECOND, 999);
}

PS: Pair class is simply a pair of two values.

Answer 2

If you have the option, you'd better avoid the horrid Java Date API, and use instead Jodatime . Here is an example:

LocalDate monthBegin = new LocalDate().withDayOfMonth(1);
LocalDate monthEnd = new LocalDate().plusMonths(1).withDayOfMonth(1).minusDays(1);

Answer 3

Try LocalDate from Java 8:

LocalDate today = LocalDate.now();
System.out.println("First day: " + today.withDayOfMonth(1));
System.out.println("Last day: " + today.withDayOfMonth(today.lengthOfMonth()));

Answer 4

Simple and Best, Try this One

Calendar calendar = Calendar.getInstance();
            calendar.add(Calendar.MONTH, 0);
            calendar.set(Calendar.DATE, calendar.getActualMinimum(Calendar.DAY_OF_MONTH));
            Date monthFirstDay = calendar.getTime();
            calendar.set(Calendar.DATE, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
            Date monthLastDay = calendar.getTime();

        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
        String startDateStr = df.format(monthFirstDay);
        String endDateStr = df.format(monthLastDay);

        Log.e("DateFirstLast",startDateStr+" "+endDateStr);

Answer 5

Calendar c = Calendar.getInstance();
    int year = c.get(Calendar.YEAR);
    int month = c.get(Calendar.MONTH);
    int day = 1;
    c.set(year, month, day);
    int numOfDaysInMonth = c.getActualMaximum(Calendar.DAY_OF_MONTH);
    System.out.println("First Day of month: " + c.getTime());
    c.add(Calendar.DAY_OF_MONTH, numOfDaysInMonth-1);
    System.out.println("Last Day of month: " + c.getTime());

Answer 6

With the date4j library :

dt.getStartOfMonth();
dt.getEndOfMonth();

Answer 7

Try this Code

Calendar calendar = Calendar.getInstance();
int yearpart = 2010;
int monthPart = 11;
int dateDay = 1;
calendar.set(yearpart, monthPart, dateDay);
int numOfDaysInMonth = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
System.out.println("Number of Days: " + numOfDaysInMonth);
System.out.println("First Day of month: " + calendar.getTime());
calendar.add(Calendar.DAY_OF_MONTH, numOfDaysInMonth-1);
System.out.println("Last Day of month: " + calendar.getTime());

Hope it helps.

Answer 8

Date begining, ending;
Calendar calendar_start =BusinessUnitUtility.getCalendarForNow();
  calendar_start.set(Calendar.DAY_OF_MONTH,calendar_start.getActualMinimum(Calendar.DAY_OF_MONTH));
  begining = calendar_start.getTime();
  String start= DateDifference.dateToString(begining,"dd-MMM-yyyy");//sdf.format(begining);


   //            for End Date of month
  Calendar calendar_end = BusinessUnitUtility.getCalendarForNow();
  calendar_end.set(Calendar.DAY_OF_MONTH,calendar_end.getActualMaximum(Calendar.DAY_OF_MONTH));
      ending = calendar_end.getTime();
      String end=DateDifference.dateToString(ending,"dd-MMM-yyyy");//or sdf.format(end);

enter code here



public static Calendar getCalendarForNow() {
        Calendar calendar = GregorianCalendar.getInstance();
        calendar.setTime(new Date());
        return calendar;
    }

Answer 9

For Java 8+, below method will given current month first & last dates as LocalDate instances.

public static LocalDate getCurrentMonthFirstDate() {
    return LocalDate.ofEpochDay(System.currentTimeMillis() / (24 * 60 * 60 * 1000) ).withDayOfMonth(1);
}

public static LocalDate getCurrentMonthLastDate() {
    return LocalDate.ofEpochDay(System.currentTimeMillis() / (24 * 60 * 60 * 1000) ).plusMonths(1).withDayOfMonth(1).minusDays(1);
}

Side note: Using LocalDate.ofEpochDay(...) instead of LocalDate.now() gives much improved performance. Also, using the millis-in-a-day expression instead of the end value, which is 86400000 is performing better. I initially thought the latter would perform better than the the expression :P

Answer 10

public static void main(String[] args) 
    {
        LocalDate today = LocalDate.now();
        System.out.println("First day: " + 
today.withDayOfMonth(1));
        System.out.println("Last day: " + today.withDayOfMonth(today.lengthOfMonth()))
    }

Answer 11

You can implement it as below:

public void FirstAndLastDate() {

    SimpleDateFormat sdf = new SimpleDateFormat("yyy-MM-dd");
    //start date of month
    calendarStart = Calendar.getInstance();
    calendarStart.set(Integer.parseInt((new SimpleDateFormat("yyyy")).format(new Date().getTime()))
            , Integer.parseInt((new SimpleDateFormat("MM")).format(new Date().getTime()))
            , Calendar.getInstance().getActualMinimum(Calendar.DAY_OF_MONTH));

    //End Date of month
    calendarEnd = Calendar.getInstance();
    calendarEnd.set(Integer.parseInt((new SimpleDateFormat("yyyy")).format(new Date().getTime()))
            , Integer.parseInt((new SimpleDateFormat("MM")).format(new Date().getTime()))
            , Calendar.getInstance().getActualMaximum(Calendar.DAY_OF_MONTH));

    Toast.makeText(this, sdf.format(calendarStart.getTime()) + "\n" + sdf.format(calendarEnd.getTime()), Toast.LENGTH_SHORT).show();

}

Answer 12

A very simple step to get the first day and last day of the month:

    Calendar calendar = Calendar.getInstance();
    
    // Get the current date
    Date today = calendar.getTime();
    
    
    // Setting the first day of month
    calendar.set(Calendar.DAY_OF_MONTH, 1);
    Date firstDayOfMonth = calendar.getTime();

    // Move to next month  
    calendar.add(Calendar.MONTH, 1);
    // setting the 1st day of the month
    calendar.set(Calendar.DAY_OF_MONTH, 1);
    // Move a day back from the date
    calendar.add(Calendar.DATE, -1);
    Date lastDayOfMonth = calendar.getTime();

    // Formatting the date  
    DateFormat sdf = new SimpleDateFormat("dd-MMM-YY");

    String todayStr = sdf.format(today);
    String firstDayOfMonthStr = sdf.format(firstDayOfMonth);
    String lastDayOfMonthStr = sdf.format(lastDayOfMonth);
    
    System.out.println("Today            : " + todayStr);
    System.out.println("Fist Day of Month: "+firstDayOfMonthStr);
    System.out.println("Last Day of Month: "+lastDayOfMonthStr);

Answer 13

if you have java.time.YearMonth you can do:

YearMonth startYearMonth = YearMonth.now();
java.time.LocalDate startOfMonthDate = startYearMonth.atDay(1);    
java.time.LocalDate endOfMonthDate   = startYearMonth.atEndOfMonth();

Answer 14

Making it more modular, you can have one main function that calculates startDate or EndDate and than you can have individual methods to getMonthStartDate , getMonthEndDate and to getMonthStartEndDate . Use methods as per your requirement.

public static String getMonthStartEndDate(){
    String start = getMonthDate("START");
    String end = getMonthDate("END");
    String result = start + " to " + end;
    return result;
}

public static String getMonthStartDate(){
    String start = getMonthDate("START");
    return start;
}

public static String getMonthEndDate(){
    String end = getMonthDate("END");
    return end;
}

/**
 * @param filter 
 * START for start date of month e.g.  Nov 01, 2013
 * END for end date of month e.g.  Nov 30, 2013
 * @return
 */
public static String getMonthDate(String filter){
            String MMM_DD_COMMA_YYYY       = "MMM dd, yyyy";
    SimpleDateFormat sdf = new SimpleDateFormat(MMM_DD_COMMA_YYYY);
    sdf.setTimeZone(TimeZone.getTimeZone("PST"));
    sdf.format(GregorianCalendar.getInstance().getTime());

    Calendar cal =  GregorianCalendar.getInstance();
    int date = cal.getActualMinimum(Calendar.DATE);
    if("END".equalsIgnoreCase(filter)){
        date = cal.getActualMaximum(Calendar.DATE);
    }
    cal.set(Calendar.DATE, date);
    String result =  sdf.format(cal.getTime());
    System.out.println(" " + result  );

    return result;
}