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getAttribute returns NULL

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Join Date: Oct 2008

Posts: 1

Reputation: itzzmeyoyo is an unknown quantity at this point

Solved Threads: 0

itzzmeyoyo itzzmeyoyo is offline

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getAttribute returns NULL

Oct 20th, 2008

Iam not able to pass a value from servlet to jsp using setAttribute and getAttribute.

My test code :

Test1.jsp
=======

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 JSP Syntax (Toggle Plain Text) 
<%@ page language="java" contentType="text/html" %>
<html>
<head><title>Login Example</title></head> 
<body>
Enter Your Text
<hr><p>
<form name = login action="../servlet/TestServlet1" method=POST>
Your Text : <input type=text name=yourText><br>
<input type=submit value=LogIn>
</form>
</body>
</html>
<%@ page language="java" contentType="text/html" %>
<html>
<head><title>Login Example</title></head> 
<body>
Enter Your Text
<hr><p>
<form name = login action="../servlet/TestServlet1" method=POST>
Your Text : <input type=text name=yourText><br>
<input type=submit value=LogIn>
</form>
</body>
</html>

TestServlet1.java
============

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 JSP Syntax (Toggle Plain Text) 
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
 
public class TestServlet1 extends HttpServlet {
 
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
doPost(request, response);
}
 
public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
 
// initalize some variables
HttpSession session = request.getSession(true);
String userText = request.getParameter("yourText");
session.setAttribute("myText", userText);
RequestDispatcher rd = request.getRequestDispatcher("/../TEST/Test2.jsp");
rd.forward(request, response);
}
}
}
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class TestServlet1 extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
doPost(request, response);
}

public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

// initalize some variables
HttpSession session = request.getSession(true);
String userText = request.getParameter("yourText");
session.setAttribute("myText", userText);
RequestDispatcher rd = request.getRequestDispatcher("/../TEST/Test2.jsp");
rd.forward(request, response);
}
}
}

Test2.jsp
=======

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 JSP Syntax (Toggle Plain Text) 
<%@ page language="java" contentType="text/html" %>
<% String up = (String)session.getAttribute("myText"); %>
 
<html>
<head><title>Login Example</title></head> 
<body>
<% if (up == null) 
{ %>
its null again
<% } else { 
%>
<%= up %> is my text!<br>
<% } %>
</body>
</html>
<%@ page language="java" contentType="text/html" %>
<% String up = (String)session.getAttribute("myText"); %>

<html>
<head><title>Login Example</title></head> 
<body>
<% if (up == null) 
{ %>
its null again
<% } else { 
%>
<%= up %> is my text!<br>
<% } %>
</body>
</html>

All the time iam getting null from getAttribute.

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<% String up = (String)session.getAttribute("myText"); %>
<% String up = (String)session.getAttribute("myText"); %>

When i printed the sessionId in the servlet and both jsp (Test1,Test2), it showed thw same session id
the session id is same but the attributes which i set is not there...

code for printing session id
===================

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String id = session.getId();
System.out.println(id);
String id = session.getId();
System.out.println(id);

can anyone help me in this ?
Thanks in advance

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Join Date: Jun 2006

Posts: 7,620

Reputation: ~s.o.s~ has much to be proud of

Solved Threads: 468

~s.o.s~

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Failure as a human

Re: getAttribute returns NULL

Oct 22nd, 2008

Since you are using a forward, there is no need to use session variables. The HttpServletRequest is preserved when forwarding.

I don't accept change; I don't deserve to live.

•

Join Date: Oct 2008

Posts: 9

Reputation: arunmagar is an unknown quantity at this point

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arunmagar

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Newbie Poster

Re: getAttribute returns NULL

Oct 26th, 2008

instead of this
<% String up = (String)session.getAttribute("myText"); %>

try this
<% String up = session.getAttribute("myText").toString(); %>

The session attribute is of object datatype.so we have to convert it to string .

•

Join Date: Jun 2006

Posts: 7,620

Reputation: ~s.o.s~ has much to be proud of

Solved Threads: 468

~s.o.s~

Offline

Failure as a human

Re: getAttribute returns NULL

Oct 26th, 2008

> try this <% String up = session.getAttribute("myText").toString(); %> .

...which would anyways throw a NullPointerException in this case.

> The session attribute is of object datatype.so we have to convert it to string .

What? The ` session ' variable is of the type ` HttpSession '.

Last edited by ~s.o.s~; Oct 26th, 2008 at 10:11 am.

I don't accept change; I don't deserve to live.