Question

I am learning Java EE and JSP. I have created an Enterprise Application project in NetBeans.
I have the EJB project where all beans are and a WAR project where all web/client stuff is.
My problem is that the annotation @EJB does not instantiate my Bean in the WAR application. Can I use @EJB outside the EJB application?

In the EJB project, I have these files:
CustomerRemote.java

@Remote
public interface CustomerRemote {
    public Customer createCustomer();
    public Customer getCustomer(int customerId);
    public void removeCustomer();
}

CustomerBean.java

@Stateless
public class CustomerBean implements CustomerRemote {

    @PersistenceContext(unitName="testPU")
    private EntityManager entityManager;

    @Override
    public Customer createCustomer() {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    @Override
    public void removeCustomer() {        
    }

    @Override
    public Customer getCustomer(int customerId) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
}

In the WAR project, I have a file that my JSP page uses to communicate with the EJB stuff. The problem is that the CustomerRemote object is never instantiated. @EJB annotation does not seem to work because customerRemote always is null. But when instantiating it with the lookup method, it works! So why does not @EJB work?

public class CustomerProxyBean {

@EJB
private CustomerRemote customerRemote;

public CustomerProxyBean() {        
//    try {
//        InitialContext context = new InitialContext();
//        customerRemote = (CustomerRemote)context.lookup("java:app/SimpleShop-ejb/CustomerBean");
//        
//    } catch (NamingException ex) {
//        Logger.getLogger(CustomerProxyBean.class.getName()).log(Level.SEVERE, null, ex);
//    }
}

Answer 1

@EJB annotation will work only in cases where your class is container-managed, that is EJB, servlet, JSP… In your case you put it into plain old Java object (POJO) so injection will not work, as you have experienced. Write your CustomerProxyBean as a stateless session bean, and you’ll see the change.

Alternatively, if you want to avoid JNDI for some reason, you can use CDI and @Inject annotation to inject EJB and achieve wished behaviour, even in POJO:

@Inject
private CustomerRemote customerRemote;