泽西岛ClientResponse获取复合实体列表

Question

I am trying to get a Result of a List, basically a list of entities using Jersey RESTful API (Server and Client)

UserRESTClient client = new UserRESTClient();
ClientResponse response = client.getUsersByType(ClientResponse.class, String.valueOf(userType));
List<User> participants = response.getEntity(new GenericType<List<User>>() {
    });

However, the above code does not work if Entity User has a Composite Object, if for instance,

public class User {
  private UserId userId;
}
public class UserId {
  private int id;
  private int categoryId;
}

In this case, the JSON is deserialized by Jersey and returned null for the field type UserId inside Class User. I inspected the JSON returned and everything seems good at the RESTful Server end, but the nested JSON response is not clearly processed at the Client.

Any help would be greatly appreciated. I am not sure if it because of the Jackson preprocessor.

Following is the actual Code Snippet. It involves two classes Participant and ParticipantPK (primary for each Participant).

@Entity
@Table(name = "conference_participant")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "Participant.findAll", query = "SELECT p FROM Participant p"),

public class Participant implements Serializable {
  private static final long serialVersionUID = 1L;
  @EmbeddedId
  protected ParticipantPK participantPK;
}

@Embeddable
public class ParticipantPK implements Serializable {
    @Basic(optional = false)
    @NotNull
    @Column(name = "conference_id")
    private int conferenceId;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 150)
    @Column(name = "participant_sip_uri")
    private String participantSipUri;

    public ParticipantPK() {
    }

    public ParticipantPK(int conferenceId, String participantSipUri) {
        this.conferenceId = conferenceId;
        this.participantSipUri = participantSipUri;
    }

And the Code for retrieving ClientResponse,

 List<Participant> participants = response.getEntity(new GenericType<List<Participant>>() {
    });

However, the ParticipantPK (Composite PK) is null.

Answer 1

You only pasted a code snippet so I don't know if this part is excluded, but in my code I didn't have setters for the fields. I had getters, but no setters.

Without the setters, my composite objects themselves were non-null, but the members of those objects were themselves null.

Answer 2

I tried to reproduce it, but using the same data structures worked for me. What version of Jersey are you using? Is User class annotated with @XmlRootElement or are you using the POJO mapping feature?