Help with EJB DI

[Ronwaldo Cruz]

Hi,

Currently I'm getting a nullpointer exception on my servlet that uses an EJB.

Here is my servlet

import java.io.IOException;

import javax.ejb.EJB;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.jeff.ejb.IExampleSessionBean;


public class HelloServlet extends HttpServlet{
	
	@EJB
	public IExampleSessionBean bean;
	
	
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(req, resp);
	}
		
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		
		String sayhello = bean.sayHello("Bruno");
		
		req.setAttribute("sayHello", sayhello);
		
	}
}

Here is my EJB

import javax.ejb.*;

@Local
public interface IExampleSessionBean {
	String sayHello(String name);
}

import javax.ejb.Stateless;

@Stateless(mappedName="ejb/exampleStateless")
public class ExampleSessionBean implements IExampleSessionBean{
	
	public String sayHello(String name) {
		return "Hello " + name + " !";
	}

}

Here's my application.xml

  <?xml version="1.0" encoding="UTF-8"?>
<application xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:application="http://java.sun.com/xml/ns/javaee/application_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/application_5.xsd" id="Application_ID" version="5">
  <display-name> 
EnterpriseProject2</display-name>
  <module>
    <web>
      <web-uri>WebProject.war</web-uri>
      <context-root>WebProject</context-root>
    </web>
  </module>
  <module>
    <ejb>EJBProject2.jar</ejb>
  </module>
</application>  

I have deployed both the war file and the ejb jar file into a single EAR file. Is there something more I need to do? Thank you.

[Sonal Popat]

In web.xml file add servlet-name, servlet-class and servlet mapping tags.

<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>com.test.servlet.HelloServlet</servlet-class> /* package name of your HelloServlet */
</servlet>
<servlet-mapping>
<servlet-name>HelloServlet</servlet-name>
<url-pattern>/HelloServlet</url-pattern>
</servlet-mapping>

deploy both the projects independently and in your browser try the http://localhost:8080/YourWARProjectName/HelloServlet

[Ronwaldo Cruz]

Hi,

I have done this and I get null pointer exception on my servlet because the container did not inject the EJB into the servlet.

For EJB to EJB DI it works ok. I can also find the EJB remotely through JNDI.

Seems DI doesn't work in Glassfish for Web and EJB

[Jaikiran Pai]

What does your web.xml look like? See if this helps.

[Ronwaldo Cruz]

Thanks. This really helped