0 Replies Latest reply on Apr 12, 2006 7:43 AM by dapissarenko

Passing data from Servlet to JSP page

dapissarenko Apr 12, 2006 7:43 AM

Hello!

I have a servlet EnterConstantServlet, which does some operation, which might fail. If that operation fails, I want that the user comes to a JSP page enterConstantFailed.jsp, where the error should be displayed.

If the operation completes successfully, the user should be redirected to JSP page enterConstantSuccess.jsp.

The servlet code is like shown below:

public class EnterConstantServlet extends HttpServlet {
 private static final String SUCCESS_PAGE = "enterConstantSuccess.jsp";
 private static final String FAILURE_PAGE = "enterConstantFailed.jsp";
 private static final long serialVersionUID = 1L;

 public EnterConstantServlet() {
 super();
 // TODO Auto-generated constructor stub
 }

 /**
 * @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
 */
 @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
 Exception2TextualStackTrace func=null;
 PendingConstantHome home=null;
 PendingConstant pendingConstant=null;
 Context initial =null;
 String constant=null;
 Object objRef =null;

 /**
 * fetch name of the constant
 */
 constant=req.getParameter("constantName");

 /**
 * save constant in OpenCyc as pending constant
 */
 try
 {
 initial = new InitialContext();

 objRef = initial.lookup("java:comp/env/ejb/SimpleRoster");

 home = (PendingConstantHome)PortableRemoteObject.narrow(objRef, PendingConstantHome.class);

 pendingConstant = home.create();

 pendingConstant.setPendingConstantName(constant);

 resp.sendRedirect(SUCCESS_PAGE);
 }
 catch (Exception exception)
 {
 func=new Exception2TextualStackTrace();

 System.out.println("failure reason: " + func.evaluate(exception));

 resp.addHeader(FAILURE_REASON, func.evaluate(exception));
 resp.sendRedirect(FAILURE_PAGE);
 }
 }
}

Note: The return value of

func.evaluate(exception)

is not null. I see this in the log file of JBoss.

I have a problem - the failure reason (parameter FAILURE_REASON in the above code) is NOT displayed in enterConstantFailed.jsp.

enterConstantFailed.jsp looks like shown below:

<?xml version="1.0" encoding="UTF-8" ?>
<%--
 $Author: user $
 $Revision: 1.2 $
 $Date: 2006/04/11 20:51:35 $
 $Id: enterConstantFailed.jsp,v 1.2 2006/04/11 20:51:35 user Exp $
 $Log: enterConstantFailed.jsp,v $
 Revision 1.2 2006/04/11 20:51:35 user
 Added routine for displaying failure reason.

 Revision 1.1 2006/04/11 20:29:58 user
 Initial commit.

--%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
 pageEncoding="UTF-8"%>
<%@ include file="header.jsp" %>

<h1>????????? ?????? ??? ????? ?????????</h1>
<p>????? ?????? ???????? ????.</p>
<pre><%= request.getParameter(intranet.dapissarenko.com.WriteImageServlet.FAILURE_REASON) %></pre>

<%@ include file="footer.jsp" %>

What should I do in order for the failure reason to be displayed in enterConstantFailed.jsp?

Thanks in advance

Dmitri Pissarenko

PS: This is the code of header.jsp:

<?xml version="1.0" encoding="UTF-8" ?>
<!--
 $Author: user $
 $Revision: 1.2 $
 $Date: 2006/04/04 21:39:40 $
 $Id: header.jsp,v 1.2 2006/04/04 21:39:40 user Exp $
 $Log: header.jsp,v $
 Revision 1.2 2006/04/04 21:39:40 user
 Added link to sanSanych.jsp.

 Revision 1.1 2006/04/02 22:56:57 user
 Initial commit.

-->
<%@ page language="java" contentType="text/html; charset=UTF-8"
 pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="ru" lang="ru-RU">
 <head>
 <meta http-equiv="content-type" content="application/xhtml+xml; charset=UTF-8" />
 <meta name="author" content="haran" />
 <meta name="generator" content="haran" />

 <link rel="stylesheet" type="text/css" href="prosimii-screen.css" media="screen, tv, projection" title="Default" />
 <link rel="stylesheet alternative" type="text/css" href="prosimii-print.css" media="screen" title="Print Preview" />
 <link rel="stylesheet" type="text/css" href="prosimii-print.css" media="print" />

 <title>?????????? ???? ??????? ?????????</title>
 </head>

 <body>
 <!-- For non-visual user agents: -->
 <div id="top"><a href="#main-copy" class="doNotDisplay doNotPrint">Skip to main content.</a></div>

 <!-- ##### Header ##### -->

 <div id="header">
 <div class="superHeader">
 <span></span>
 <a href="http://dapissarenko.com" title="Dmitri Pissarenko">??????????? ???? ??????? ?????????</a>
 </div>

 <div class="midHeader">
 <h1 class="headerTitle" lang="la">??????? ?????????</h1>
 <div class="headerSubTitle">
 ?????????? ????
 </div>

 <br class="doNotDisplay doNotPrint" />


 </div>

 <div class="subHeader">
 <span class="doNotDisplay">Navigation:</span>
 <a href="enterTime.jsp">?????? ????? ??????</a> |
 <a href="sanSanych.jsp">??? ?????</a> |
 <a href="./index.html">?????????? ???????????</a>
 </div>
 </div>

 <!-- ##### Main Copy ##### -->

 <div id="main-copy">
 <div class="rowOfBoxes">
 <div class="twoThirds noBorderOnLeft">

PPS: This is the code of footer.jsp:

<?xml version="1.0" encoding="UTF-8" ?>
<!--
 $Author: user $
 $Revision: 1.2 $
 $Date: 2006/04/02 23:07:06 $
 $Id: footer.jsp,v 1.2 2006/04/02 23:07:06 user Exp $
 $Log: footer.jsp,v $
 Revision 1.2 2006/04/02 23:07:06 user
 Fixed encoding problems.

 Revision 1.1 2006/04/02 22:56:57 user
 Initial commit.

-->
<%@ page language="java" contentType="text/html; charset=UTF-8"
 pageEncoding="UTF-8"%>
 <!-- ##### Main text comes here ##### -->

 </div>
 </div>
 </div>

 <!-- ##### Footer ##### -->

 <div id="footer">
 <span class="doNotPrint">
 ?? ???? ???????? ?????? ???? ???????? ?????? ?? ????
 <a href="mailto:office@dapissarenko.com">office@dapissarenko.com</a><br />
 </span>

 <strong>???????? ??????? »</strong> <%= java.text.DateFormat.getDateTimeInstance(java.text.DateFormat.DEFAULT, java.text.DateFormat.DEFAULT, new java.util.Locale("ru")).format(new java.util.Date()) %>
 </div>
 </body>
</html>