Question

If possible I would prefer a joda or non-joda solution for the scenario below

Lets say if my week starts on 02/05/2012 and the given current date is 02/22/2011. I need to calculate the week start and end date for the given current date. So my solution should have the week start as 02/19 and week ends at 02/25.
For simplicity, I have set my week start here as 02/05/2011 but it could be any day potentially and my week always has 7 days.

My existing code is below but doesnt seem to work as expected.

public Interval getWeekInterval(Date calendarStartDate, Date date)
{
    Calendar sDate = Calendar.getInstance();
    sDate.setTime(getMidnightDate(calendarStartDate));

    Calendar eDate = Calendar.getInstance();
    eDate.setTime(date);

    Calendar weekStartDate = (Calendar) sDate.clone();
    logger.debug("Date:" + sDate.getTime());
    while (sDate.before(eDate)) {
        weekStartDate = sDate;
        sDate.add(Calendar.DAY_OF_WEEK_IN_MONTH, 1);
    }

    return new Interval(weekStartDate.getTime(), sDate.getTime());
}

Answer 1

Try this (pseudo-code):

// How many days gone after reference date (a known week-start date)
daysGone  = today - referenceDate;

// A new week starts after each 7 days
dayOfWeek = daysGone % 7;

// Now, we know today is which day of the week.
// We can find start & end days of this week with ease
weekStart = today - dayOfWeek;
weekEnd   = weekStart + 6;

Now, we can shorten all of this to two lines:

weekStart = today - ((today - referenceDate) % 7);
weekEnd   = weekStart + 6;

Note that we subtracted date values like integers to show algorithm. You have to write your java code properly.