Passing Values between JSP Pages

JSP Tutorials - Herong's Tutorial Examples

∟Passing Values between JSP Pages

This section provides a tutorial example on how to use different ways to pass values between JSP pages: putting values in 'session' or 'application' objects, or putting values at the end of redirect URL.

There are many ways to pass values from one page to the next page. For example,

Putting values into the session object.
Putting values into the application object
Putting values at the end of the redirect URL.

In the following example, I am showing you a tutorial example on how to use different ways to pass values between JSP pages. In this example, I have two JSP pages working together as a registration process. Here is the first JSP page, RegForm.jspx:

<?xml version="1.0"?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.3">
<!-- RegForm.jspx
 - Copyright (c) 2006 HerongYang.com. All Rights Reserved.
-->
<jsp:directive.page contentType="text/html"/>
<jsp:declaration><![CDATA[
   private String getItem(String queryString, String key) {
      String value = null;
      if (queryString!=null) {
         int i = queryString.indexOf(key);
         if (i>-1) {
            i = i + key.length();
            int j = queryString.indexOf("&",i);
            if (j>-1) {
               value = queryString.substring(i,j);
            } else {
               value = queryString.substring(i);
            }
            if (value.startsWith("=")) {
               value = value.replaceFirst("=","");
            }
         }
      }
      return value;
   }
]]></jsp:declaration>
<jsp:scriptlet><![CDATA[
   String lastUser = (String) application.getAttribute("name");
   if (lastUser==null) {
      lastUser = "Nobody";
      application.setAttribute("name",lastUser);
   }
   String queryString = request.getQueryString();
   String submit = getItem(queryString,"submit");
   if (submit!=null && submit.equals("Submit")) {
   // Collecting the input data
      session.setAttribute("name",getItem(queryString,"name"));
      session.setAttribute("pass",getItem(queryString,"pass"));
      application.setAttribute("name",getItem(queryString,"name"));
      response.sendRedirect("RegDone.jspx?color="
         +getItem(queryString,"color"));
   } else {
   // Presenting the registration form
      out.print("<html><body>");
      out.print("<b>Registration Form</b>:<br/>");
      out.print("<form action=RegForm.jspx method=get>");
      out.print("Login Name:");
      out.print("<input type=text size=16 name=name><br/>");
      out.print("Password:");
      out.print("<input type=text size=16 name=pass><br/>");
      out.print("Favor Color:");
      out.print("<input type=text size=16 name=color><br/>");
      out.print("<input type=submit name=submit value=Submit></br>");
      out.print("</form>");
      out.print("Your session ID is "+session.getId()+"<br/>");
      out.print("Last user on the server: "+lastUser+"<br/>");
      out.print("</body></html>");
   }
]]></jsp:scriptlet>
</jsp:root>

Here is the second JSP page, RegDone.jspx:

<?xml version="1.0"?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.3">
<!-- RegDone.jspx
 - Copyright (c) 2006 HerongYang.com. All Rights Reserved.
-->
<jsp:directive.page contentType="text/html"/>
<jsp:declaration><![CDATA[
   private String getItem(String queryString, String key) {
      String value = null;
      if (queryString!=null) {
         int i = queryString.indexOf(key);
         if (i>-1) {
            i = i + key.length();
            int j = queryString.indexOf("&",i);
            if (j>-1) {
               value = queryString.substring(i,j);
            } else {
               value = queryString.substring(i);
            }
            if (value.startsWith("=")) {
               value = value.replaceFirst("=","");
            }
         }
      }
      return value;
   }
]]></jsp:declaration>
<jsp:scriptlet><![CDATA[
   out.print("<html><body>");
   String lastUser = (String) application.getAttribute("name");
   String queryString = request.getQueryString();
   out.print("<b>Thank you for registering with us</b>:<br/>");
   out.print("Login Name: "+(String)session.getAttribute("name")
      +"<br/>");
   out.print("Password: "+(String)session.getAttribute("pass")
      +"<br/>");
   out.print("Favor Color: "+getItem(queryString,"color")+"<br/>");
   out.print("Your session ID is "+session.getId()+"<br/>");
   out.print("Last user on the server: "+lastUser+"<br/>");
   out.print("</body></html>");
]]></jsp:scriptlet>
</jsp:root>