Question

当另一个表中只有一个外键时，如何从另一个表中获取对象？

我有以下实体：

public class ViolationFactor extends BaseEntity {

    @Column(name = "czynnik")
    private String factor;

    @Column(name = "stopien")
    private float degree;

    @JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
//  @JsonBackReference
    @OneToOne(mappedBy = "violationFactor", cascade = CascadeType.ALL, fetch = FetchType.LAZY, optional = false)
    private IncidentAssessmentFactor incidentAssessmentFactor;
}

public class IncidentAssessmentFactor extends BaseEntity {

    @Column(name="komentarz")
    private String comment;

    @Column(name="czynnik_wybrany")
    private Boolean factorIsSelected;

    @Column(name = "wartosc_wybrana")
    private float value;

//  @JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
    @OneToOne(fetch = FetchType.LAZY)
    @JoinColumn(name="ocena_naruszenia_wynik_id", updatable=false, insertable=false)
    private IncidentAssessment incidentAssessment;

//  @JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
//  @JsonManagedReference
    @OneToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "czynnik_naruszen_id", unique = true)
    private ViolationFactor violationFactor;
}

表ViolationFactor没有指向IncidentAssessmentFactor的任何外键-它只是一本字典。 IncidentAssessmentFactor与ViolationFactor无关。

如何从IncidentAssessmentFactor中删除IncidentAssessmentFactor属性？我只希望有一个@OneToOne单向绑定。现在我有了循环依赖：违规因素->突发事件评估因素->违规因素当执行到DTO的映射时，我得到堆栈溢出错误：

是否可以拥有财产IncidentAssessmentFactor eventAssertsFactor；仅在ViolationFactor实体中？

我的存储库：

public interface ViolationCriterionRepository extends JpaRepository<ViolationCriterion, Long> {

    @Query("select vc from ViolationCriterion vc join vc.violationFactors vf join vf.incidentAssessmentFactor iaf join iaf.incidentAssessment ia where ia.incidentAssessmentId = ?1 group by vc ")
    List<ViolationCriterion> findIncidentAssessmentByIncidentAssessmentId(Long incidentId);
}

java.lang.StackOverflowError：在为null org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke（JavassistLazyInitializer.java:84）〜[hibernate-core-5.2.16.Final.jar：5.2.16.Final]在 pl.ultimo.web.odo.ODOBackend.incidents.entities.IncidentAssessment _ $$ _ jvst6f1_32.getIncidentAssessmentId（IncidentAssessment _ $$ _ jvst6f1_32.java）〜[classes / :?]在 pl.ultimo.web.odo.ODOBackend.incidents.mapper.ViolationCriterionMapperImpl.incidentAssessmentToIncidentAssessmentDto（ViolationCriterionMapperImpl.java:150）〜[classes / :?]在 pl.ultimo.web.odo.ODOBackend.incidents.mapper.ViolationCriterionMapperImpl.incidentAssessmentFactorToIncidentAssessmentFactorDto（ViolationCriterionMapperImpl.java:169）〜[classes / :?]

@OneToOne在另一个表中具有反向外键

0 个答案: