Get the Difference between 2 dates

[Ikasari Widiyanto]

Hi,

I would like to how how to calculate the difference between 2 dates by using jsp... thanks..
best regards,
Ika

[Paul Sturrock]

Rememebr that a Date object is actually a long representing the number of milliseconds since the "epoch" (1/1/1970 00:00). So:

long difference = date1.getTime() - date2.getTime();

will give you the millisecond difference between the two. Then it only takes a little arithmetic to get this in a more user-friendly format.

[Bear Bibeault]

Moving to the Java in General (intermediate) forum.

[Chengwei Lee]

When you say difference, are you trying to find out the number of seconds/minutes/hours/days/months/years between 2 dates?

By taking their differences & getting the results in milliseconds, you could then divide by the right factor to get that difference.

But, if I'm not mistaken, the Calendar class can solve this too. Check it out.

HTH.

[Ikasari Widiyanto]

hehe.. thanks.. but I got 1 problem.. the dates is in string format... how to change this to date format?

[Jeroen Wenting]

DateFormat

[Srinivasa Raghavan]

Check with the class "SimlpeDateFormat"

[Ikasari Widiyanto]

I think its the other way around.. my date is in string then how to convert it to date format

[Srinivasa Raghavan]

Use the SimpleDateFormat, construct the date & use the parse method in that class.

Here it is.

[Ikasari Widiyanto]

ok.. thanks.. I've tried the code but it gives me this error:
Error: java.text.ParseException: Unparseable date: "2005-3-1"
my code:
String datestart=request.getParameter("datestart");
DateFormat formatter = new SimpleDateFormat("yyMMddHHmmssZ");
try {
// parse utc into Date
java.util.Date date = formatter.parse(datestart);
out.println(date);
}
catch(ParseException pe) {
out.println( "\nError: " + pe.toString() );
}

[Horatio Westock]

You are trying to parse "2005-3-1" with "yyMMddHHmmssZ". If you read the SimpleDateFormat, there are example of how to build a suitable pattern.

[Karthikeyan Rajendraprasad]

it should be

DateFormat formatter = new SimpleDateFormat("yy-MM-dd");

to get the your date format("2005-3-1") to be parsed correctly

[Pedro Garcia]

Here is another example, you can customizing the format and language

  Locale locale= new Locale("es","ES");
  DateFormat formatter = new SimpleDateFormat("dd MMM yy", locale);
  Date date = (Date)formatter.parse("01/29/02");
  Calendar cal=date.getTime();