How to calculate time difference in JSP

<% @ Page contentType = "text/html; charset = gb2312" %>

<% @ Page import = "java. text. *" %>

<% @ Page import = "java. util. *" %>

<%

// Convert a string to a time type (the string can be of any type, as long as it is consistent with the format in SimpleDateFormat)

Java. text. SimpleDateFormat sdf = new java. text. SimpleDateFormat ("M/dd/yyyy hh: mm: ss a", java. util. Locale. US );

Java. util. Date d = sdf. parse ("5/13/2003 10:31:37 AM ");

Out. println (d );

Out. println ("<br/> ");

SimpleDateFormat formatter = new SimpleDateFormat ("yyyy-MM-dd HH: mm: ss ");

String mDateTime1 = formatter. format (d );

Out. println (mDateTime1 );

Out. println ("<br/> ");

Out. println (d. getTime ());

Out. println ("<br/> ");

// Current time

Calendar cal = Calendar. getInstance ();

// SimpleDateFormat formatter = new SimpleDateFormat ("yyyy-MM-dd HH: mm: ss ");

SimpleDateFormat formatter = new SimpleDateFormat ("yyyy-MM-dd HH: mm: ss g e d f w W a e f ");

String mDateTime = formatter. format (cal. getTime ());

Out. println (mDateTime );

Out. println ("<br/> ");

// Date 1 year ago

Java. util. Date myDate = new java. util. Date ();

Long myTime = (myDate. getTime ()/1000)-60*60*24*365;

MyDate. setTime (myTime * 1000 );

String mDate = formatter. format (myDate );

Out. println (mDate );

Out. println ("<br/> ");

// Tomorrow's date

MyDate = new java. util. Date ();

MyTime = (myDate. getTime ()/1000) + 60*60*24;

MyDate. setTime (myTime * 1000 );

MDate = formatter. format (myDate );

Out. println (mDate );

Out. println ("<br/> ");

// Number of days between two times

SimpleDateFormat myFormatter = new SimpleDateFormat ("yyyy-MM-dd ");

Java. util. Date date = myFormatter. parse ("2003-05-1 ");

Java. util. Date mydate = myFormatter. parse ("1899-12-30 ");

Long day = (date. getTime ()-mydate. getTime ()/(24*60*60*1000 );

Out. println (day );

Out. println ("<br/> ");

// Add half an hour

SimpleDateFormat format = new SimpleDateFormat ("yyyy-MM-dd hh: mm: ss ");

Java. util. Date date1 = format. parse ("23:16:00 ");

Long Time = (date1.getTime ()/1000) + 60*30;

Date1.setTime (Time * 1000 );

String mydate1 = formatter. format (date1 );

Out. println (mydate1 );

Out. println ("<br/> ");

// Calculate the date of year, month, and week

SimpleDateFormat formatter2 = new SimpleDateFormat ("yyyy-mm f e ");

Java. util. Date date2 = formatter2.parse ("Friday 2003-05 ");

SimpleDateFormat formatter3 = new SimpleDateFormat ("yyyy-MM-dd ");

String mydate2 = formatter3.format (date2 );

Out. println (mydate2 );

Out. println ("<br/> ");

// The day of the week

Mydate = myFormatter. parse ("2001-1-1 ");

SimpleDateFormat formatter4 = new SimpleDateFormat ("E ");

String mydate3 = formatter4.format (mydate );

Out. println (mydate3 );

Out. println ("<br/> ");

%>
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Another
Import java. text. DateFormat;
Import java. text. ParseException;
Import java. util. Date;
Class test
{
Public static void main (String [] args) throws ParseException
{
DateFormat df = DateFormat. getDateInstance ();
String str1 = "2002-3-4 ";
String str2 = "2002-7-12 ";
Long l1 = df. parse (str1). getTime (); // converts a string to a time
Long l2 = df. parse (str2). getTime ();
Long l3 = 0; // Time Interval
If (l1> l2) // determine the time sequence
{
L3 = L1-L2;
} Else
{
L3 = l2-l1;
}
L3 = l3/(60*60*24*1000 );
System. out. println (str1 + "and" + str2 + "separated by" + l3 + "days! ");
}
}