NullPointerException avec createNamedQuery()
	
	
		Bonjour tout le monde,
j' ai cree une petite application ejb. 
Pour le moment j'ai fait un formulaire de login avec deux champs (user,mdp):
	Citation:
	
		
		
			public class Login extends javax.swing.JFrame {
    @EJB
    private static CommunicationRemote communicationBean;
    Client ClientConnecte;
    /** Creates new form Login */
    public Login() {
        initComponents();
        communicationBean=new CommunicationBean();
    }
private void LoginActionPerformed(java.awt.event.ActionEvent evt) {                                         
// TODO add your handling code here:
    if(!TxtUser.getText().equals("") &&  !TxtPass.getText().equals(""))
        {            
            try {
                   communicationBean.findByUserMdpAdmin(TxtUser.getText(), TxtPass.getText());
                   System.out.println("Administrateur connecté");                                                              
                    LInfo.setText("Info :Connection Réussie");   
                
            } catch (ExceptionCommunication ex) {
                LInfo.setText(ex.getMessage());
            }
        }
} 
			
		
	
 Mon Bean Session:
	Citation:
	
		
		
			@Stateful
@EJB
public class CommunicationBean implements CommunicationRemote {
@EJB
    private AdministratorFacadeLocal administratorFacade=new AdministratorFacade();
...
public void findByUserMdpAdmin(String user, String pass) throws ExceptionCommunication{
        Administrator c= administratorFacade.findByUserMdp(user, pass);
    }
...
			
		
	
 Ma facade Administrator :
	Citation:
	
		
		
			@Stateless
public class AdministratorFacade implements AdministratorFacadeLocal {
    @PersistenceContext
    private EntityManager em;
...
public Administrator findByUserMdp(String user, String pass) throws ExceptionCommunication{
        try
        {            
            System.out.println("Login:"+user.toString()+" /Pass:"+pass.toString());
            Query qu=null;
            qu=em.createNamedQuery("Administrator.findUserMdp");
            qu.setParameter("login", user);
            qu.setParameter("password", pass);
            return (Administrator) qu.getSingleResult();            
        }
        catch(NoResultException e)
        {
            throw new ExceptionCommunication("Login/Password Incorrect(s)");
        }
    }
...
			
		
	
 C est a cette ligne: qu=em.createNamedQuery("Administrator.findUserMdp"); que j obtient l erreur suivante : Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException.
Mon Entity creer avec netbeans (BD oracle):
	Citation:
	
		
		
			@Entity
@Table(name = "ADMINISTRATOR")
@NamedQueries({@NamedQuery(name = "Administrator.findUserMdp", 
query = "SELECT c FROM ADMINISTRATOR c WHERE c.login = :login and c.password = :password" ),...})
public class Administrator implements Serializable {
    private static final long serialVersionUID = 1L;
    @Column(name = "LOGIN", nullable = false)
    private String login;
    @Column(name = "PASSWORD", nullable = false)
    private String password;
    @Id
    @Column(name = "IDADMIN", nullable = false)
    private BigDecimal idadmin;
    public Administrator() {
    }
...
			
		
	
 Est-ce que quelqu'un sait pourquoi j'obtient toujours le NullPointerException?
Merci