java.lang.IllegalArgumentException: Named query not found:

I got the following code

@Stateless
public class BondecomandeDAO {

    @PersistenceContext
    private EntityManager em;

    public Bondecommande findBCbyid(int id)
    {
         Query q =em.createNamedQuery("select bc from Bondecommande bc where bc.idbc = :idbc");
         q.setParameter("idbc", id);
         return  (Bondecommande) q.getResultList().get(0);
     }
}

and

@Entity
@Table(name="bondecommande")
public class Bondecommande  implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name="idbc")
    private int idbc;
    @Column(name="devise")
    private String devise;
    @Column(name="modepaiement")
    private String modepaiement;
    @Column(name="modelivraison")
    private String modelivraison;
    @Column(name="delaipaiement")
    private int delaipaiement;

      ////other attributes , getters and setters 
}

When I try to run the function findBCbyid(int id) I get this error

java.lang.IllegalArgumentException: Named query not found: select bc from Bondecommande bc where bc.idbc = :idbc

Although I used this named query in an another project, and it worked, what could be the problem here?

Use em.createQuery(... instead of em.createNamedQuery()

If you work with named queries (what I would recommend) you have to place the query inside a @NamedQuery annotation on your entity class.