CODEWITHSUNDEEP
javaservlets
user123
user123

Reputation: 101

Getting null value on request.getAttribute

Hi I have a servlet class like this

public class DBConnection extends HttpServlet {
   protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException 
   {

      resp.setContentType("text/html");
      req.setAttribute("Message","Message from servlet page");

      req.getRequestDispatcher("/index.jsp").forward(req,resp);

   }
}

calling servlet on index.jsp page like this

<% String Msg= (String)request.getAttribute("Message");
out.println("<p> Servlet communicated message to JSP: "+ Msg + "</p>");%>

This in my web.xml file

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
    <display-name>dbconnection</display-name>
    <welcome-file-list>
    <welcome-file>Login.html
    </welcome-file>
    </welcome-file-list>

    <servlet>
        <servlet-name>DBConnection</servlet-name>
        <servlet-class>DBConnection</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>DBConnection</servlet-name>
        <url-pattern>/DBConnection</url-pattern>
    </servlet-mapping>
</web-app>

I am getting a null value .. can anyone help me?

Upvotes: 1

Views: 1576

Answers (3)

Guna
Guna

Reputation: 21

You are not calling your servlet in url that you are trying to invoke Try as suggested by Yubi.

Example: If your url pattern is 

<url-pattern>/TestingServlet</url-pattern>

in your web.xml to execute your servlet get/post in that servlet u should use urlpattern

    `http://yourserverhost:port/ServletTest/TestingServlet`

ServletTest is your application context and TestingServlet is your url pattern for your Servlet.

  <servlet>
    <description></description>
    <display-name>TestingServlet</display-name>
    <servlet-name>TestingServlet</servlet-name>
    <servlet-class>TestingServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>TestingServlet</servlet-name>
    **<url-pattern>/TestingServlet</url-pattern>**
  </servlet-mapping>

Upvotes: 0

Yubaraj
Yubaraj

Reputation: 3988

You are getting null value because you are not accessing with right url.

Suppose you have url like following:

http://localhost:8080/TestWeb/

where your project name is TestWeb. If you had tried with above url you are getting null value because request is not comming from servlet. So you need to use like following url

http://localhost:8080/TestWeb/DBConnection

Then only you will get right output. Please try it.

Upvotes: 1

GbGbGbGbEB
GbGbGbGbEB

Reputation: 56

You can access the attributes defined in the servlet using Expression Language.

Inside JSP:

<p> Servlet communicated message to JSP: ${Message} </p>

Servlet:

RequestDispatcher rd;
resp.setContentType("text/html");
req.setAttribute("Message","Message from servlet page");
rd = req.getRequestDispatcher("/index.jsp");
rd.forward(req,resp);

Upvotes: 0

Related Questions