JSP Days between user selected dates

Question

I have been working on this for two days solid now. I have gone through numerous posts here but they are not much help to me.

I need to take two dates from a user and calculate the number of days between them. I understand that JODA-time is best and that is not an option ( I am sure the point of this exercise is to go through pain...). I am not worried about leap year or daylight savings time as of yet. I take things in small steps. I have included the code for getting the input but I have not been able to form the syntax correctly to compare the two inputs. Any nudge in the correct direction is appreciated.

<%@page import="java.util.Calendar" %>
<%@page contentType="text/html" import="java.util.*" %>
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="utf-8" />
    <title>Date Comarision</title>
    <link rel="stylesheet"   href="http://code.jquery.com/ui/1.10.2/themes/smoothness/jquery-ui.css" />
    <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
    <script src="http://code.jquery.com/ui/1.10.2/jquery-ui.js"></script>

    <script>
        $(function() {
          $( ".datepicker" ).datepicker();
        });
    </script>

</head>
<body>
     <form action="Calculate.jsp" method="post">

        <p>First Date: <input type="text" name="firstdate"  class="datepicker" /></p>
        <p>Second Date: <input type="text" name="seconddate" class="datepicker" /></p>

         <input type="submit" value="Calculate">
      </form>
</body>
</html>

Latest for comparing (not pretty):

<%@page import="sun.util.calendar.LocalGregorianCalendar.Date"%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Calculate</title>
 </head>
 <body>
    <h1>Calculate</h1>
 <center>

 <!--This is where the issues start. I know I can't be forming this correctly: -->

 <%
     int Date1= Date.parseInt(request.getParameter("firstdate"));
     int Date2= Date.parseInt(request.getParameter("seconddate"));
 %>

 <BR>

 <%
     out.println("----- " )+Date1.compareTo(Date2)+("----");
 %>
</center>

</body>
</html>

Some hints: 1. Use a Servlet to compute the time difference and then redirect to the result page - don't use scriptlets. 2. Java 8 introduced the handy [ChronoUnit.between](https://docs.oracle.com/javase/8/docs/api/java/time/temporal/ChronoUnit.html#between-java.time.temporal.Temporal-java.time.temporal.Temporal-) method (`DAYS.between(date1, date2)`). For older versions of Java check [this answer](http://stackoverflow.com/a/20165708/664577). — Anthony Accioly, Aug 29 '15 at 21:18
I finished the project! Thank you for pointing me the right direction! it helped me get it on my own. — Luis Ramos, Aug 30 '15 at 05:21
Hi Luis, you are very welcome. Please take the time to post your own answer and accept it if you think other people can benefit from it. — Anthony Accioly, Aug 30 '15 at 09:41

score 1 · Accepted Answer · answered Aug 31 '15 at 10:19

Here is everything, it works great. Now I want to go make it look good. Thank you for pointing me in the right direction without doing it for me!!!

<%@page import="java.util.concurrent.TimeUnit"%>
<%@page import="java.util.Calendar" %>
<%@page contentType="text/html" import="java.util.*" %>

<!DOCTYPE html>

<html lang="en">

<head>

 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 

<title>Date Comparison</title>
  <%--
        Note: Including a claender for the user to selcet desired dates    from
  --%>
<link rel="stylesheet" href="http://code.jquery.com/ui/1.10.2/themes/smoothness/jquery-ui.css" />

 <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
 <script src="http://code.jquery.com/ui/1.10.2/jquery-ui.js"></script>

 <%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>

 <script>     
     $(function() {
     $( ".datepicker" ).datepicker();
                  });
</script>

</head>

<body>

    <h1>Select two dates</h1>

        <form action="CalculateDate.jsp" method="post">

            <p>First Date: <input type="date" name="firstdate" class="datepicker" /></p>

            <p>Second Date: <input type="date" name="seconddate" class="datepicker" /></p>

            <input type="submit" value="Calculate">

        </form>

</body>



</html>

<%@page contentType="text/html" pageEncoding="UTF-8"%>

<!DOCTYPE html>

<html>

<head>

    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

    <title>Calculate</title>

</head>

    <body>

        <h1>Calculate</h1>

    </body>

</html>

<%@page import="java.text.DateFormat"%>
<%@page import="java.util.*"%>
<%@page import="java.text.SimpleDateFormat"%>
<%@page import="java.util.Calendar" %>    

 <%

    String date1 =request.getParameter("firstdate");

    String date2 =request.getParameter("seconddate");

        SimpleDateFormat dateformat = new SimpleDateFormat ("E    yyyy.MM.dd"); //SDF to display output with day of week

    Date displaydate1=new Date(date1); //Turning the inputed date from string
                                       //to date format to be used for the output
    Date displaydate2=new Date(date2);

      int differenceInDays = (int) ((displaydate2.getTime() - displaydate1.getTime())/(1000*60*60*24));//common method to calculate number of days

    out.println("Between " +dateformat.format(displaydate1)+ " and " +dateformat.format(displaydate2)+ " there are " +differenceInDays+ " days");

 %>

JSP Days between user selected dates

1 Answers1