References lost at persistence time

Question

Below follow my entities and their relationships:

Order:

@Entity
@Table(name = "encomenda")
@XmlRootElement(name = "objeto")
@XmlAccessorType(XmlAccessType.FIELD)
public class Encomenda {

    @Getter
    @Setter
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Getter
    @Setter
    @Pattern(regexp = "[A-z]{2}\\d{9}[A-z]{2}", message = "O código não é válido")
    @Size(min = 13, max = 13, message = "É permitido 13 caracteres")
    @Column(nullable = false, length = 13)
    @NotBlank(message = "Nome não pode estar em branco")
    @XmlElement(name = "numero")
    private String codigo;

    @Getter
    @Setter
    @XmlElement(name = "evento")
    @OneToMany(mappedBy = "encomenda", targetEntity = Evento.class, cascade = CascadeType.ALL)
    private Collection<Evento> eventos;

    @Getter
    @Setter
    @Column
    private String loja;

    @Getter
    @Setter
    @XmlElement
    @Column
    private String erro;

Event:

@EqualsAndHashCode
@Entity
@Table(name = "evento")
@XmlRootElement(name="evento")
@XmlAccessorType(XmlAccessType.FIELD)
public class Evento {

    @Getter
    @Setter
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Getter
    @Setter
    @Column
    @XmlElement(name="data")
    private String dataOcorrencia;

    @Getter
    @Setter
    @Column
    @XmlElement(name="hora")
    private String horaOcorrencia;

    @Getter
    @Setter
    @Column
    @XmlElement
    private String descricao;

    @Getter
    @Setter
    @Column
    @XmlElement
    private String local;

    @Getter
    @Setter
    @Column
    @XmlElement
    private String cidade;

    @Getter
    @Setter
    @Column
    @XmlElement
    private String uf;

    @Getter
    @Setter
    @OneToOne(mappedBy="evento",cascade = CascadeType.ALL)
    @XmlElement(name="destino")
    private Destino destino;

    @Getter
    @Setter
    @ManyToOne
    private Encomenda encomenda;

In the database I have the tables event and order. In the event table have order_id which is FK. The big problem that by persisting the object order your id is normally generated as in the event table the id is generated, but the order field is null. Does anyone know how to resolve ?

The object is filled through an xml, the controller is like this:

@ManagedBean
@ViewScoped
public class EncomendaController {

    @Getter
    @Setter
    private Encomenda encomenda;

    @Getter
    @Setter
    private Collection<Encomenda> objetos;

    @Inject
    private EncomendaService service;

    @PostConstruct
    public void novo() {
        encomenda = new Encomenda();
    }

    public void salvar() throws IOException, SOAPException {
        if (encomenda.getId() == null) {
            try {
                popularObjeto(encomenda.getCodigo());
                service.insert(encomenda);
                JsfUtils.addInfoMessage("encomenda.cadastrada");
                encomenda = new Encomenda();
            } catch (Exception e) {
                e.printStackTrace();
            }
        } else {
            service.update(encomenda);
        }
    }

    private Encomenda popularObjeto(String codigo) throws IOException, SOAPException, JAXBException {
        String xml = RoboCorreios.consultarCodigo(codigo);

        JAXBContext context = JAXBContext.newInstance(Encomenda.class);
        Unmarshaller unmarshaller = context.createUnmarshaller();
        Encomenda objeto = (Encomenda) unmarshaller.unmarshal(new StringReader(xml));
        final boolean objetoExiste = objeto.getErro() == null ? true : false;

        if (objetoExiste) {
            setEncomenda(objeto);
            return encomenda;
        } else {
            encomenda.setErro("Objeto não localizado");
            return encomenda;
        }
    }

}

My Service:

@Stateless
@LocalBean
public class EncomendaService extends ServiceBase {

    public void insert(Encomenda objeto) {
        this.em.persist(objeto);
    }

    public void update(Encomenda objeto) {
        this.em.merge(objeto);
    }

Answer 1

The problem is that you did not associate the order reference in the event listing. One way to do this is to add a foreach to load the object into each item in the event list:

public void salvar() throws IOException, SOAPException {
        if (encomenda.getId() == null) {
            try {
                popularObjeto(encomenda.getCodigo());

                for (Evento evento : encomenda.getEventos()) {
                    evento.setEncomenda(encomenda);
                }
                service.insert(encomenda);
                JsfUtils.addInfoMessage("encomenda.cadastrada");
                encomenda = new Encomenda();
            } catch (Exception e) {
                e.printStackTrace();
            }
        } else {
            service.update(encomenda);
        }
    }

With this change the same order created will be associated to each of the events.