How to access init parameter from web.xml in servlet

[berender mavi]

Hi All,

I am using a init param named as Name in servlet parameter.But when i am running follwing code in doGet

System.out.println("Name is"+getServletConfig().getInitParameter("Name"));

getting null.why ? can you please tell me?

my web.xml is as follows:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" 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">
 <display-name>MyServlet</display-name>
 <context-param>
  <param-name>emailContext</param-name>
  <param-value>[e-mail]</param-value>
 </context-param>
 <servlet>
  <servlet-name>ConfigTest</servlet-name>
  <servlet-class>config.ConfigTest</servlet-class>
  <init-param>
   <param-name>Name</param-name>
   <param-value>Manish Arora</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
 </servlet>
 <welcome-file-list>
  <welcome-file>index.html</welcome-file>
  <welcome-file>index.htm</welcome-file>
  <welcome-file>index.jsp</welcome-file>
  <welcome-file>default.html</welcome-file>
  <welcome-file>default.htm</welcome-file>
  <welcome-file>default.jsp</welcome-file>
 </welcome-file-list>
</web-app>

one more thing when i am overriding the init() method and using the same code in it.
why am getting 2 times printing for one statement in init().First time i am getting the correct result from web.xml but in second printing it's again null.

Please help.Thanks

[Victor M. Pereira]

If your using the same code in the init, why override it?

The init method sets the servletConfig, you should check if your servletConfig has what is supposed to have.

When you make changes in the DD, you should try to redeploy it. Some servers don't have the automatic hot redeploy.

Try stopping the server, wait 30 seconds and start it again.

[berender mavi]

Still getting the same null.

My code is as follows

package config;

import java.io.IOException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/ConfigTest")
public class ConfigTest extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    public ConfigTest() {
        super();
    }
    public void init(){
    	System.out.println("Name is"+getServletConfig().getInitParameter("Name"));
    	
    }
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		System.out.println(getServletConfig().getServletContext().getInitParameter("emailContext"));
		System.out.println(getServletConfig().getInitParameter("Name"));
		
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

}

and output on console is

Name isManish Arora
Mar 5, 2012 3:09:21 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-6080"]
Mar 5, 2012 3:09:22 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["ajp-bio-6090"]
Mar 5, 2012 3:09:22 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 9758 ms
Name isnull
[e-mail]
null

[Victor M. Pereira]

May sound dumb, but could you try deleting <load-on-startup>1</load-on-startup> line from your DD. Is a running theory bu tjust try it.

[Bharat Kasodariya]

I think you should override
public void init(ServletConfig config) method to get config param.

The code will be like

public void init(ServletConfig config){
// Store the ServletConfig object and log the initialization
super.init(config);

System.out.println("Name is"+config.getInitParameter("Name"));

}