session.getAttribute from servlet and display in html

Question

I have a login servlet that takes values from a login html file and redirects immediately to sessiondemo.html.

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

  public class logIn extends HttpServlet {
    public void doGet(HttpServletRequest req, HttpServletResponse res)
                      throws ServletException, IOException {

      res.setContentType("text/html");
      PrintWriter out = res.getWriter();
      HttpSession session = req.getSession(true);

      //getting the value(s) from HTML
      String fname = req.getParameter("fname");
      String lname = req.getParameter("lname");
      String email = req.getParameter("email");
      String address = req.getParameter("address");

      //Storing the values in Session
      session.setAttribute("FirstName", fname );
      session.setAttribute("LastName", lname );
      session.setAttribute("Email", email);
      session.setAttribute("address", address);

      res.sendRedirect("http://localhost:8080/apps/sessiondemo.html");
      out.close(); 
    }
  }

What I cant figure out is, I want to display the first and last name in the sessiondemo html. I know the code has to be written in the seesiondemo html but it is not working.

Here is what I tried:

<% session.getAttribute("FirstName", fname);
        out.println("You are logged in as" + fname + "!");%>

XML files

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>
  <description>Test examples</description>
  <display-name>My Servlets</display-name>

 <servlet>
  <servlet-name>GET</servlet-name>
  <servlet-class>GET</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>GET</servlet-name>
  <url-pattern>/GET</url-pattern>
</servlet-mapping>

 <servlet>
  <servlet-name>POST</servlet-name>
  <servlet-class>POST</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>POST</servlet-name>
  <url-pattern>/POST</url-pattern>
</servlet-mapping>

 <servlet>
  <servlet-name>Cart</servlet-name>
  <servlet-class>Cart</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>Cart</servlet-name>
  <url-pattern>/Cart</url-pattern>
</servlet-mapping>

<servlet>
  <servlet-name>logIn</servlet-name>
  <servlet-class>logIn</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>logIn</servlet-name>
  <url-pattern>/logIn</url-pattern>
</servlet-mapping>


</web-app>

Why did you try _that_? What is the declaration of `HttpSession#getAttribute(...)`? How many arguments does it accept? — Sotirios Delimanolis, Oct 30 '14 at 15:32
I just gave it a shot, if you know how to display the first name in html, help me ? — Reda93, Oct 30 '14 at 15:34
That shows me that you haven't done your research. [`HttpSession#getAttribute(String)`](http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpSession.html#getAttribute%28java.lang.String%29) only takes one argument, a `String` value, not two. — Sotirios Delimanolis, Oct 30 '14 at 15:42
I have put the session.getattribute in the html that I want it to display in — Reda93, Oct 30 '14 at 15:50
An HTML file is not the same thing as a JSP file. Scriptlets are not evaluated. — Sotirios Delimanolis, Oct 30 '14 at 15:51

kirti · Answer 1 · 2014-10-30T15:43:33.067

1

For session try using this...

<% request.getSession().getAttribute("FirstName") %>

edited Oct 30 '14 at 15:43

answered Oct 30 '14 at 15:35

kirti

4,499
4
31
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I am supposed to be working with sessions, so if you know how to do it in sessions, plz tell me ? – Reda93 Oct 30 '14 at 15:38
I tried with only FirstName but didnt work so I just gave it a shot, I know it only takes one argument and I know its wrong, instead of telling me its wrong, plz you can at least tell me how to fix it ? – Reda93 Oct 30 '14 at 15:45

score 1 · Answer 2 · edited May 23 '17 at 11:53

1

Forget about scriptlets, avoid its usage. Use Expression language instead:

<div id="divUser">
    Welcome ${FirstName} ${LastName}
</div>

Here, ${FirstName} will be replaced by the attribute with name "FirstName" stored in one of these scopes:

Page Scope
Request Scope
Session Scope
Application Scope

This will only work when using it in JSP. HTML is static, so it's not compiled nor evaluated by the application server, and you will get no results.

More info:

How to pass parameter to jsp:include via c:set? What are the scopes of the variables in JSP?

You should also specify that you're using at least Servlets 2.4 to enable Expression Language. Currently, Servlet is in version 3.1, but you can use Servlets 3.0 in your Jetty 9+ installation. Change your web.xml file to have this statement at the top:

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
      version="3.0"> 

    <description>Test examples</description>
    <display-name>My Servlets</display-name>

    <!-- rest of the content of your web.xml -->

</web-app>

You can check the jetty servlet version compatibility here: Jetty Version Comparison Table

edited May 23 '17 at 11:53

Community

1
1

answered Oct 30 '14 at 15:50

Luiggi Mendoza

85,076
16
154
332

@Reda93 why are you using plain html in the first place? That's the root of all your problems. – Luiggi Mendoza Oct 30 '14 at 15:53
@Reda93 you're redirecting to *sessiondemo.html*. It should be *sessiondemo.jsp*. JSP is dynamic HTML. – Luiggi Mendoza Oct 30 '14 at 15:55
so if I change sessiondemo.html to sessiondemo.jsp, will it work ? – Reda93 Oct 30 '14 at 15:56
@Reda93 yes, change the extension of your file and the code where you redirect from html to jsp, and it will work. And again, don't use scriptlets. – Luiggi Mendoza Oct 30 '14 at 15:58
Ok I changed it, but the values where not taken, it just displayed Welcome ${FirstName} ${LastName} – Reda93 Oct 30 '14 at 16:00
@Reda93 which application server are you using. Which version of servlet and JSP are you using in your project? Are you sure you changed the extension of your file as well? – Luiggi Mendoza Oct 30 '14 at 16:00
I am sure I changed the extension, and I am using Jetty-9 application for server ? – Reda93 Oct 30 '14 at 16:02
Then something looks odd. This should work as expected. Could you please edit your question and provide the content of web.xml file? – Luiggi Mendoza Oct 30 '14 at 16:03
@Reda93 one more question, are you using maven to build your project? – Luiggi Mendoza Oct 30 '14 at 16:16
I am not using maven ! – Reda93 Oct 30 '14 at 16:17
@Reda93 answer updated. And please avoid using exclamation symbols, don't get too excited. – Luiggi Mendoza Oct 30 '14 at 16:30

score 0 · Answer 3 · answered Jul 12 '18 at 02:26

0

not using localhost ，replace with ip eg: 'http://localhost:8080/apps/sessiondemo.html 'replace 'http://127.0.0.1:8080/apps/sessiondemo.html' and try again.

answered Jul 12 '18 at 02:26

wendy

1

session.getAttribute from servlet and display in html

3 Answers3