Java: how do I check if a Date is within a certain range?

Question

I have a series of ranges with start dates and end dates. I want to check to see if a date is within that range.

Date.before() and Date.after() seem to be a little a

Answer 1

  public class TestDate {

    public static void main(String[] args) {
    // TODO Auto-generated method stub

    String fromDate = "18-FEB-2018";
    String toDate = "20-FEB-2018";

    String requestDate = "19/02/2018";  
    System.out.println(checkBetween(requestDate,fromDate, toDate));
}

public static boolean checkBetween(String dateToCheck, String startDate, String endDate) {
    boolean res = false;
    SimpleDateFormat fmt1 = new SimpleDateFormat("dd-MMM-yyyy"); //22-05-2013
    SimpleDateFormat fmt2 = new SimpleDateFormat("dd/MM/yyyy"); //22-05-2013
    try {
     Date requestDate = fmt2.parse(dateToCheck);
     Date fromDate = fmt1.parse(startDate);
     Date toDate = fmt1.parse(endDate);
     res = requestDate.compareTo(fromDate) >= 0 && requestDate.compareTo(toDate) <=0;
    }catch(ParseException pex){
        pex.printStackTrace();
    }
    return res;
   }
 }

Answer 2

boolean isWithinRange(Date testDate) {
   return !(testDate.before(startDate) || testDate.after(endDate));
}

Doesn't seem that awkward to me. Note that I wrote it that way instead of

return testDate.after(startDate) && testDate.before(endDate);

so it would work even if testDate was exactly equal to one of the end cases.

Answer 3

For covering my case -> I've got a range start & end date, and dates list that can be as partly in provided range, as fully (overlapping).

Solution covered with tests:

/**
 * Check has any of quote work days in provided range.
 *
 * @param startDate inclusively
 * @param endDate   inclusively
 *
 * @return true if any in provided range inclusively
 */
public boolean hasAnyWorkdaysInRange(LocalDate startDate, LocalDate endDate) {
    if (CollectionUtils.isEmpty(workdays)) {
        return false;
    }

    LocalDate firstWorkDay = getFirstWorkDay().getDate();
    LocalDate lastWorkDay = getLastWorkDay().getDate();

    return (firstWorkDay.isBefore(endDate) || firstWorkDay.equals(endDate))
            && (lastWorkDay.isAfter(startDate) || lastWorkDay.equals(startDate));
}

Answer 4

That's the correct way. Calendars work the same way. The best I could offer you (based on your example) is this:

boolean isWithinRange(Date testDate) {
    return testDate.getTime() >= startDate.getTime() &&
             testDate.getTime() <= endDate.getTime();
}

Date.getTime() returns the number of milliseconds since 1/1/1970 00:00:00 GMT, and is a long so it's easily comparable.

Answer 5

This was clearer to me,

// declare calendar outside the scope of isWithinRange() so that we initialize it only once
private Calendar calendar = Calendar.getInstance();

public boolean isWithinRange(Date date, Date startDate, Date endDate) {

    calendar.setTime(startDate);
    int startDayOfYear = calendar.get(Calendar.DAY_OF_YEAR); // first day is 1, last day is 365
    int startYear = calendar.get(Calendar.YEAR);

    calendar.setTime(endDate);
    int endDayOfYear = calendar.get(Calendar.DAY_OF_YEAR);
    int endYear = calendar.get(Calendar.YEAR);

    calendar.setTime(date);
    int dayOfYear = calendar.get(Calendar.DAY_OF_YEAR);
    int year = calendar.get(Calendar.YEAR);

    return (year > startYear && year < endYear) // year is within the range
            || (year == startYear && dayOfYear >= startDayOfYear) // year is same as start year, check day as well
            || (year == endYear && dayOfYear < endDayOfYear); // year is same as end year, check day as well

}

Answer 6

An easy way is to convert the dates into milliseconds after January 1, 1970 (use Date.getTime()) and then compare these values.