package pawel;
import java.util.*;
import java.text.*;
public final class TimeStamp {
 private String str;
 final static private SimpleDateFormat format
   = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss");
 public TimeStamp() {
   str = format.format(new java.util.Date());
 }
 public String toString() {
   return str;
 }
 public boolean equals(Object o) {
   return o instanceof TimeStamp && str.equals(""+o);
 }
 public int hashCode() {
   return str.hashCode();
 }
 public static void main(String args[]) {
   System.out.println(""+new TimeStamp());
 }
}

Opalinski
opalpa@gmail.com
http://www.geocities.com/opalpaweb/

I don't think it is correct to refer to something that contains only a year,
month, and day as a timestamp; I believe that a timestamp also needs to
contain hours, minutes, seconds, and fractional seconds (sometimes
milliseconds, sometimes microseconds, sometimes nanoseconds). However,
perhaps that is nitpicking.

The following code will determine the current month, day, and year for you:

       GregorianCalendar now = new GregorianCalendar();
       int intCurrentMonth = now.get(GregorianCalendar.MONTH) + 1;
       int intCurrentDay = now.get(GregorianCalendar.DAY_OF_MONTH);
       int intCurrentYear = now.get(GregorianCalendar.YEAR);

Remember that months are 0-based in Java, i.e. January is month 0, so I've
added 1 to the month so that January is 1, February is 2, etc.

Now, all you need to do is write some code to:
- convert the ints to Strings
- prepend zeroes to the values of the month and day - after all, you don't
want 1-1-2006 for January 1 2006, you want 2006-01-01
- concatenate the padded values together into a String with your filename.

For instance, something like this:

   String currentMonth = Integer.toString(intCurrentMonth);
   if (intCurrentMonth <= 9) currentMonth = "0"+currentMonth;
   String currentDay = Integer.toString(intCurrentDay);
   if (intCurrentDay <= 9) currentDay = "0"+currentDay;
   String currentYear = Integer.toString(intCurrentYear);

   String currentDate = currentMonth + "-" + currentDay + "-" currentYear;

   String fullFileName =  "filename"+currentDate+".txt";

Rhino

"Sandeep" <sandeepsinghal@gmail.com> wrote...

People seem to be interpreting your question as "how do create and
concatenate a date string" which I think we can see it isn't.  Your main
problem (it seems to me) is to recognize whether there is a date on the
filename presently.  You have to derive a function to test for the presence
of a date which doesn't mistake some legitimate filename for your
concatenated string.

It isn't hard to do but you should isolate it into a single method
IsDatePresent() or something like that so you can adjust the code if you get
a false positive at some point.  You know it should be attached to the end
of the filename, it should follow a 99-99-9999 convention and the filename
cannot be shorter than 11 characters or there couldn't be a date string
attached (it had to have at least  one character initially).

If the filename passed was "test00-00-1234" you can see this might get by as
it coincidentally matches.  In that case you could improve IsDatePresent(),
add a test for valid dates and this example would report False.

Tom

see http://mindprod.com/jgloss/file.html

File.setLastModified

It is always easier to explain these problems with a few examples.
Is this what you mean?

rabbit.txt ->  rabbit01-22-2006.txt
rabbit12-31-2005 -> rabbit01-22-2006.txt

First I would use iso date format YYYY-MM-DD , rather than MM-DD-YYYY
so there is no ambiguity about DD-MM or MM-DD. It also sorts in order
properly in directory listings if you have dups.  You migh consider
putting the date on the front, depending on your sorting needs.

You have several problems:

1. deterimine if there is a date on the end already. You could do that
with a regex or just by testing each char in turn to see if 0-9 or -.
as appropriate for the slot. If there is one, either remove it an
replace, or leave it alone. If there isn't, add one.
see http://mindprod.com/jgloss/regex.html

2. generate an iso Date string with today's date.
See http://mindprod.com/jgloss/calendar.html#TODAY
for the code.

3. You may need to rename existing files. Use File.rename
See http://mindprod.com/jgloss/file.html

4. you may need to redate (touch) existing files.  Use
File.setLastModified ( System.currentTimeInMillis())
See http://mindprod.com/jgloss/file.html
http://mindprod.com/jgloss/time.html