Null pointer exception while EJB injection

I wrote very simple web application with one stateless Ejb, the interesting moment comes when I implement interface - ejb dependency injection does not work: web.xml ``` <?xml version="1.0" ?> <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"> <display-name>Archetype Created Web Application</display-name> <servlet> <servlet-name>simpleController</servlet-name> <servlet-class>com.SimpleController</servlet-class> </servlet> <servlet-mapping> <servlet-name>simpleController</servlet-name> <url-pattern>*.job</url-pattern> </servlet-mapping> </web-app> ``` Servlet class ``` package com; import javax.ejb.EJB; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; public class SimpleController extends HttpServlet { @EJB private SimpleBean bean; @Override protected void doPost (HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { resp.getWriter().println(bean.getSomeString()); } @Override protected void doGet (HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doPost(req, resp); } } ``` bean ``` package com; import javax.ejb.Stateless; @Stateless public class SimpleBean /*implements Simple*/ { public String getSomeString(){ return "axaxaxa!"; } } ``` inteface ``` package com; import javax.ejb.Remote; //@Local @Remote public interface Simple { String getSomeString(); } ``` So when I uncoment "implements Simple" I got NullPointerException (with @Remote or @Local annotation in interface), another case I get "axaxaxa!". Why it happens? I read the Ejb class must implement intefaces. I use TommEEcas Application Server.