Бесконечная рекурсия с выпуском Джексона JSON и Hibernate JPA ⇐ JAVA

[Anonymous]

При попытке преобразовать объект JPA, который имеет двунаправленную ассоциацию в JSON, я продолжаю получать < /p>
org.codehaus.jackson.map.JsonMappingException: Infinite recursion (StackOverflowError)
< /code>
Все, что я нашел,-это этот поток, который в основном завершается рекомендацией избежать двунаправленных ассоциаций. У кого-нибудь есть идея обходного пути для этой весенней ошибки?@Entity
@Table(name = "ta_trainee", uniqueConstraints = {@UniqueConstraint(columnNames = {"id"})})
public class Trainee extends BusinessObject {

@Id
@GeneratedValue(strategy = GenerationType.TABLE)
@Column(name = "id", nullable = false)
private Integer id;

@Column(name = "name", nullable = true)
private String name;

@Column(name = "surname", nullable = true)
private String surname;

@OneToMany(mappedBy = "trainee", fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@Column(nullable = true)
private Set bodyStats;

@OneToMany(mappedBy = "trainee", fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@Column(nullable = true)
private Set trainings;

@OneToMany(mappedBy = "trainee", fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@Column(nullable = true)
private Set exerciseTypes;

public Trainee() {
super();
}

//... getters/setters ...
}
< /code>
Бизнес-объект 2: < /p>
import javax.persistence.*;
import java.util.Date;

@Entity
@Table(name = "ta_bodystat", uniqueConstraints = {@UniqueConstraint(columnNames = {"id"})})
public class BodyStat extends BusinessObject {

@Id
@GeneratedValue(strategy = GenerationType.TABLE)
@Column(name = "id", nullable = false)
private Integer id;

@Column(name = "height", nullable = true)
private Float height;

@Column(name = "measuretime", nullable = false)
@Temporal(TemporalType.TIMESTAMP)
private Date measureTime;

@ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@JoinColumn(name="trainee_fk")
private Trainee trainee;
}
< /code>
контроллер: < /p>
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletResponse;
import javax.validation.ConstraintViolation;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

@Controller
@RequestMapping(value = "/trainees")
public class TraineesController {

final Logger logger = LoggerFactory.getLogger(TraineesController.class);

private Map trainees = new ConcurrentHashMap();

@Autowired
private ITraineeDAO traineeDAO;

/**
* Return json repres. of all trainees
*/
@RequestMapping(value = "/getAllTrainees", method = RequestMethod.GET)
@ResponseBody
public Collection getAllTrainees() {
Collection allTrainees = this.traineeDAO.getAll();

this.logger.debug("A total of " + allTrainees.size() + " trainees was read from db");

return allTrainees;
}
}
< /code>
jpa-внедрение стажера dao: < /p>
@Repository
@Transactional
public class TraineeDAO implements ITraineeDAO {

@PersistenceContext
private EntityManager em;

@Transactional
public Trainee save(Trainee trainee) {
em.persist(trainee);
return trainee;
}

@Transactional(readOnly = true)
public Collection getAll() {
return (Collection) em.createQuery("SELECT t FROM Trainee t").getResultList();
}
}
< /code>
persistence.xml

false










Подробнее здесь: https://stackoverflow.com/questions/332 ... -jpa-issue