Need to change Calendar to dd/mm/yyyy format

[Kartik Tal]

Hi All,

Am having a string which is in dd/mm/yyyy format which I had parsed to Date and then to Calendar and written some logic.
Now am not able to change the output of Calendar to dd/mm/yyyy format.

  
import java.text.ParseException;
import java.util.Date;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;

public class ChangeDate {
	public static void main(String args[]) throws ParseException
	{
		DateFormat df = new SimpleDateFormat("dd/MM/yyyy"); 
		Calendar cal = Calendar.getInstance();
		StringBuffer str=new StringBuffer();
		try 
		{    
                        str.append("27/8/2009");
                        Date today = df.parse("27/8/2009");
                        cal.setTime(today);
			cal.set (Calendar.DAY_OF_WEEK, Calendar.MONDAY);
                        // [b]HERE I NEED A LOGIC WHERE I CAN CONVERT THE "cal" TO DD/MM/YYYY FORMAT.[/b]
		}
		catch (ParseException e)
		{
		}
 	}
}

[Jesper de Jong]

A Calendar does not have a format itself.

You used SimpleDateFormat to parse a date string into a Date object (which you then used to set the calendar with). To convert a date back to a string, you use the SimpleDateFormat object again, but you call format(...) instead of parse(...). For example:

String text = df.format(cal.getTime());

Note that the method getTime() of class Calendar gives you a Date object, which you can pass to the format(...) method of class SimpleDateFormat to convert it to a String.

[Gamini Sirisena]

Hi guys,
Couldn't figure this out yet.

I get the following when I run this modified.. why is there a difference in the month?

27/08/2009
27/7/2009

 import java.text.ParseException;
import java.util.Date;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Locale;


public class ChangeDate {
    public static void main(String args[]) throws ParseException {
        DateFormat df = new SimpleDateFormat("dd/MM/yyyy"); 
        Calendar cal = Calendar.getInstance();

        try 
        {    
            Date today = df.parse("27/8/2009");

            cal.setTime(today);
            // cal.set (Calendar.DAY_OF_WEEK, Calendar.MONDAY);


            Date dt = cal.getTime();
            DateFormat ndf = new SimpleDateFormat("dd/MM/yyyy");
            String str2 = ndf.format(dt);



            System.out.println(str2);

            System.out.println(
cal.get(Calendar.DAY_OF_MONTH) + "/"+ 
cal.get(Calendar.MONTH) + "/" + 
cal.get(Calendar.YEAR));

        } catch (ParseException e)
        {}
    }
}   

[Jesper de Jong]

Is there a reason why you don't want to do it with a SimpleDateFormat object as I proposed ?

Months in the Java Calendar class are 0-based: 0 = January, 1 = February, ..., 7 = August, ..., 11 = December. So if you do cal.get(Calendar.MONTH), you'll get a number from 0 to 11, not 1 to 12. You need to add 1 yourself if you want to interpret this as a regular month number yourself.

[Gamini Sirisena]

Howdy cowboy,
Your proposal is good!

And your explanation is better!

Thanks.

[Ramses Butarbutar]

Gamini,
Just share..
I hope this function help you more to understand how to interpret as a regular month number.

    
	public static String getMonthYearInNumbers(Date date){
		Calendar cal = Calendar.getInstance();
		if(date == null){
			date = new Date();
		}
		cal.setTime(date);
		int intMonth = (cal.get(Calendar.MONTH)+1);
		String strMonth = (intMonth<10)?"0"+intMonth:""+intMonth;
        return cal.get(Calendar.YEAR)+strMonth;
	}