Pass parameters from servlet to jsp using HTTPServletRequest return null

Question

I'm trying to pass parameters from servlet to JSP using HTTPServletRequest but no luck. Someone can explain me where am I wrong?

Here the servlet: HelloServlet

package net.codejava;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * Servlet implementation class HelloServlet
 */
public class HelloServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request,
                         HttpServletResponse response)
                         throws ServletException, IOException {

        request.setAttribute("name", "name1");
        request.setAttribute("surname", "surname1");
        request.getRequestDispatcher("index.jsp").forward(request, response);

    }

}

Here the JSP: JSP ("HelloServlet/index.jsp")

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>HelloWorld Index</title>
</head>
<body>
    Welcome <%= request.getAttribute("name") %>
</body>
</html>

and the web.xml: web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee" version="2.5">
    <servlet>
        <servlet-name>helloservlet</servlet-name>
        <servlet-class>net.codejava.HelloServlet</servlet-class>
        <jsp-file>/HelloServlet/index.jsp</jsp-file>        
    </servlet>
    <servlet-mapping>
        <servlet-name>helloservlet</servlet-name>
        <url-pattern>/HelloServlet</url-pattern>
    </servlet-mapping>
</web-app>

RESULT

Welcome null

try using request.getSession().setAttribute and request.getSession().getAttribute — Nishad K Ahamed, Dec 21 '15 at 11:05
@NishadKAhamed What a random solution. Don't just throw solutions. Do you know the reason for current behaviour ? — Suresh Atta, Dec 21 '15 at 11:07
@sᴜʀᴇsʜ ᴀᴛᴛᴀ this is not a solution, i just give a suggestion to check if that works or not. That is why i just commented instead of posting it as an answer. Also, please try to think an answer the question instead of wasting time in finding mistakes. — Nishad K Ahamed, Dec 21 '15 at 11:10
@NishadKAhamed I don't say anything, if you are sure that, "Finding mistake is a waste of time" — Suresh Atta, Dec 21 '15 at 11:11
put System.out doGet method and check please. Jsp file may Direct calling. — Gurkan Yesilyurt, Dec 21 '15 at 11:25
@Trenza try using response.sendRedirect("index.jsp") for redirection instead of requestDispatcher — Nishad K Ahamed, Dec 21 '15 at 11:25
@GurkanYesilyurt Could You explain better? What do you mean? — dp.carlo, Dec 21 '15 at 11:27
are you sure the Helloservlet is being called? tag remove. You already have requestdistpacher. finally, where do you keep jsp files. — Gurkan Yesilyurt, Dec 21 '15 at 11:44
To clear out a terminology mistake: those things are called attributes, not parameters. Look, the method is named `setAttribute()`, not `setParameter()`. — BalusC, Dec 21 '15 at 12:19

score 0 · Accepted Answer · answered Dec 21 '15 at 12:00

0

Actually your action is never get called. Try changing the following parts in your code.

Updated web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee" version="2.5">
    <servlet>
        <servlet-name>helloservlet</servlet-name>
        <servlet-class>net.codejava.HelloServlet</servlet-class>
   </servlet>
    <servlet-mapping>
        <servlet-name>helloservlet</servlet-name>
        <url-pattern>*.htm</url-pattern>
    </servlet-mapping>
</web-app>

and call your action by

http://localhost:8080/HelloServlet/index.htm

answered Dec 21 '15 at 12:00

Nishad K Ahamed

1,374
15
25

why I need to call htm file instead of jsp? – dp.carlo Dec 21 '15 at 13:01
its not a file, just a action path. You can chnage it to any value in web.xml url mapping. Its just a sample. – Nishad K Ahamed Dec 21 '15 at 15:43

Pass parameters from servlet to jsp using HTTPServletRequest return null

1 Answers1