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Java Calendar date interval

Can someone please provide me code to help me achieve the following:

Given any date (example: 02-12-2009), I'd like to return String array where the first value of the array is the first date in the associated week (02-08-2009) and the second value is the last date in the associated week  (02-14-2009). This would be based on a week that starts on Sunday and ends on Saturday every time. Also, I need this to work during leap years and non-leap years. Thanks for your help.  
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1 Solution
see the following for getting the first day of the week


you can then just loop adding a day each time and using a DateFormat to format the date.


Let me know if you need a hand putting it all together

jrwalker2Author Commented:
I attached my code so far. I have not gotten it to work yet. I have a few problems. First, when I create the initial Gregorian calendar, it does not appear to be following the 0-based month as stated in the javadoc. Second, the first day and the last day in the associated week are not correct. Please help. Thanks  

Actual Output
Current date: 1/19/2009
First day of week: 1/26/2009
Last day of week: 2/5/2009

Expected Output
Current date: 2/19/2009  <-------------I thought that GregorianCaledar month  is 0-based (i.e., Feb=1)
First day of week: 2/15/2009 <----------This is the Sunday of that week
Last day of week: 2/21/2009 <------------This is the Saturday of that week

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.SimpleTimeZone;
import java.util.TimeZone;
public class DateUtil 
	public static void main(String [] args)
		 //Input: February 19, 2009
		GregorianCalendar calendar = new GregorianCalendar(2009,1,19);
		 //Get the interval
		DateUtil dateUtil = new DateUtil();
		String [] interval = dateUtil.getWeekInterval(calendar);
		System.out.println("First day of week: " + interval[0]);
		System.out.println("Last day of week: " + interval[1]);
	private String[] getWeekInterval(GregorianCalendar cal)
		int day;
		int month;
		int year;
		String firstDate;
		String lastDate;
		//Current date 
		day = cal.get(Calendar.DAY_OF_MONTH);
		month = cal.get(Calendar.MONTH);
		year = cal.get(Calendar.YEAR);
		System.out.println("Current date: " + month +"/"+day+"/"+year);
		//First Day of the week 
		Calendar firstDateofTheWeek = getFirstDayOfThisWeek(cal);
		day = firstDateofTheWeek.get(Calendar.DAY_OF_MONTH);
		month = firstDateofTheWeek.get(Calendar.MONTH);
		year = firstDateofTheWeek.get(Calendar.YEAR);
		firstDate = month +"/"+day+"/"+year;
		//Last Day of the week 
		Calendar lastDateofTheWeek = getLastDayOfThisWeek(cal);
		day = lastDateofTheWeek.get(Calendar.DAY_OF_MONTH);
		month = lastDateofTheWeek.get(Calendar.MONTH);
		year = lastDateofTheWeek.get(Calendar.YEAR);
		lastDate = month +"/"+day+"/"+year;
		String [] interval = {firstDate,lastDate};
		return interval;
	private Calendar getFirstDayOfThisWeek(GregorianCalendar cal) 
		cal.add(Calendar.DAY_OF_YEAR, Calendar.SATURDAY);
		return cal;
	private Calendar getLastDayOfThisWeek(GregorianCalendar cal) 
		cal.add(Calendar.DAY_OF_YEAR, Calendar.SATURDAY);
		return cal;

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       private DateFormat df = new SimpleDateFormat("MM/dd/yyyy");
        private String[] getWeekInterval(Calendar cal)
           // find start of week

           Calendar start = Caledar.getInstance();
           start.set(Calendar.DAY_OF_WEEK, cal.getActualMinimum(Calendar.DAY_OF_WEEK));

           // find end of week

           Calendar end = Caledar.getInstance();
           end.set(Calendar.DAY_OF_WEEK, cal.getActualMaximum(Calendar.DAY_OF_WEEK));

           // format start and end date and return

           return new String[] { df.format(start), df.format(end) };

jrwalker2Author Commented:
This is great!!! The only thing that I had to change

 return new String[] { df.format(start), df.format(end) };


return new String[] { df.format(start.getTime()), df.format(end.getTime()) };

I had to do this in order to use the formatter. Thank you! Your help is very much appreciated.
I made that mistake on purpose to make sure you understood how it worked ;)


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