@EJB injection within JSF managed-bean returns null object
Hi there,
there are some posts out there about @EJB injection but after many tries, I still can't get it to work.
The injected object is always null.
I got the lookup method working yesterday but amazingly it's not working anymore today after re-deploying.
Env:
- sun-jdk-1.5.0.10
- jboss AS 4.0.4
Packaging:
--EAR
-JAR (EJB app)
META-INF/
--ejb-jar.xml
--persistence.xml
src/
--session/
-IBookingManager.java
-bean/
BookingManagerBean.java
-WAR (web tier)
src/
--business/
-Disp.java
--session/
WebContent/
--META-INF/
--WEB-INF/
-faces-config.xml
-web.xml
--index.jsp
--IBookingManager.java
EJB app. files:
persistence.xml:
<?xml version="1.0"?>
<persistence version="1.0">
<persistence-unit name="EJB-EX">
<jta-data-source>java:EJB-EX-DS</jta-data-source>
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.hbm2ddl.auto" value="create-drop" />
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLInnoDBDialect" />
<property name="hibernate.show_sql" value="true"></property>
</properties>
</persistence-unit>
</persistence>
ejb-jar.xml:
<?xml version="1.0" encoding="UTF-8"?>
<ejb-jar></ejb-jar>
session/IBookingManager.java:
package session;
publicinterface IBookingManager{
public String getHW();
//some other methods
}
session/bean/BookingManagerBean.java
package session.bean;
import javax.ejb.Local;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import session.IBookingManager;
@Stateless
@Local
publicclass BookingManagerBeanimplements IBookingManager{
@PersistenceContext(name="EJB-EX")
private EntityManager em;
public String getHW(){
return"kind of hello world ...";
}
//other methods definition using 'em' object
}
web tier files:
WebContent/WEB-INF/web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_5.xsd">
<display-name>
bibgoeson</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>index.jsf</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<listener>
<listener-class>org.apache.myfaces.webapp.StartupServletContextListener</listener-class>
</listener>
<servlet>
<servlet-name>abcDEF</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>abcDEF</servlet-name>
<url-pattern>*.jsf</url-pattern>
</servlet-mapping>
</web-app>
WebContent/WEB-INF/faces-config.xml:
<?xml version='1.0' encoding='UTF-8'?>
<faces-config 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-facesconfig_1_2.xsd"
version="1.2">
<application>
<locale-config>
<default-locale>en</default-locale>
</locale-config>
</application>
<!-- BEANS -->
<managed-bean>
<managed-bean-name>dis</managed-bean-name>
<managed-bean-class>business.Disp</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
</managed-bean>
<!-- /BEANS -->
</faces-config>
WebContent/index.jsp:
<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<html>
<head>
<title>title</title>
</head>
<body>
<f:view>
<h:form>
<h1>return</h1>
<h:outputText value="#{dis.first}" />
</h:form>
</f:view>
</body>
</html>
src/session/IBookingManager.java is the same as in EJB app
src/business/Disp.java:
package business;
import javax.ejb.EJB;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import session.IBookingManager;
publicclass Disp{
// <A>
//@EJB public IBookingManager bm;
// <A/>
private String first;
public String getFirst(){
// <B>
IBookingManager bm =null;
try{
Context c =new InitialContext();
c =new InitialContext();
bm = (IBookingManager) c.lookup("bibgoesonEAR/BookingManagerBean/local");
}catch (NamingException e){
// TODO Auto-generated catch block
e.printStackTrace();
}
// </B>
if ( bm ==null )
first ="bm is null.";
else
first ="go on";
return first;
}
publicvoid setFirst(String first){
this.first = first;
}
}
So from above, I'm using either part <A> or <B>.
When using <A>, the web page prints "bm is null."
When using <B>, I get a java.lang.ClassCastException on the lookup line. I can't explain because it was working yesterday..
The question is: why this weird behavior with the injection and how to make it work?
I think I'm using regular design with some sort of Facade design pattern where the managed-bean injects
the interface of the session-bean, in turn using a persistence context, nothing special huh?
Why the lookup method doesn't work anymore too?
Thanks
