I am working on a simple Java EE application.
I have class like this:
import javax.annotation.PostConstruct;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
@Stateless
public class BlogEntryDao {
EntityManager em;
@PostConstruct
public void initialize(){
EntityManagerFactory emf = Persistence.createEntityManagerFactory("Persistence");
em = emf.createEntityManager();
}
public void addNewEntry(){
Blogentry blogentry = new Blogentry();
blogentry.setTitle("Test");
blogentry.setContent("asdfasfas");
em.persist(blogentry);
}
}
So my managed bean calls this method. Until here no problems. But since the initialize method is not called, I am getting an NPE in em.persist.
Why is the initialize method not being called? I am running this on Glassfish server.
The Java EE bean annotations such as @PostConstruct
only apply to container-managed beans. If you are simply calling new BlogEntryDao
yourself, the container isn't going to intercept the creation and call the @PostConstruct
method.
(Furthermore, you'd be better off using @PersistenceContext
or @PersistenceUnit
instead of manually fetching the EntityManagerFactory
in your initialize()
method, and you should be creating an EntityManager
for each call to addNewEntry()
, since they're short-lived. Making these changes would eliminate the need for initialize()
at all.)