Java JAXB。建议正确的注释

有一个结构。我想以这种方式链接这三个实体：公司应该包含id、公司名称和部门列表，每个部门都有一个员工列表、id和部门名称。每个工人都有自己的名字、id

+Company
-int companyId
-String companyName
-Set<Department> listOfDepartments = new HashSet<Department>();

+Department
-int departmentId
-String departmentName
-Set<Worker> listOfWorkers = new HashSet<Worker>();

+Worker
-int workerId
-String workerName

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如何避免这种循环？

您的模型中存在双向关系。要解决此问题，您可以执行以下操作：

使用标准JAXB元数据的解决方案 1-

@xmltransive

您可以使用

@xmltransive

映射关系的一个方向。这将导致字段/属性不封送，从而阻止无限循环。此字段/属性也不会解组，这意味着您需要自己填充它

2-

@XmlID

/

@XmlIDREF

@XmlIDREF

是如何将共享引用映射到

JAXB

的，您可以使用它映射回指针关系

利用EclipseLink JAXB（MOXy）扩展的解决方案 注意：我是专家组的负责人和成员

对于这个用例，您可以使用MOXy的

@XmlInverseReference

扩展。它的作用类似于封送处理操作中的

@xmltransive

，但仍将填充解组操作中的值

@XmlRootElement(name="Company")
@XmlAccessorType(XmlAccessType.FIELD)
@Entity
public class Company {
    @XmlAttribute(name = "id")
    @Id @GeneratedValue(strategy = GenerationType.AUTO)
    private int companyId;
    @XmlElement(name = "companyName")
    private String companyName;

    @XmlElement(name="Department")
    @OneToMany(mappedBy = "company", cascade=CascadeType.PERSIST, fetch = FetchType.EAGER)
    private Set<Department> listOfDepartments = new HashSet<Department>();


@XmlRootElement(name="Department")
@XmlAccessorType(XmlAccessType.FIELD)
@Entity
public class Department {
    @XmlAttribute(name = "id")
    @Id @GeneratedValue(strategy = GenerationType.AUTO)
    private int idDepartment;

    @XmlElement(name = "departmentName")
    private String departmentName;

    @ManyToOne()
    @JoinColumn(name="companyId")
    private Company company;

    @XmlElement(name="Worker")
    @OneToMany(mappedBy = "department", cascade = CascadeType.PERSIST, fetch = FetchType.EAGER)
    private Set<Worker> listOfWorkers = new HashSet<Worker>();


@XmlRootElement(name="Worker")
@Entity
public class Worker {
    @Id @GeneratedValue(strategy = GenerationType.AUTO)
    private int idWorker;

    private String workerName;

    @ManyToOne
    @JoinColumn(name="departmentId")
    private Department department;

A cycle is detected in the object graph. This will cause infinitely deep XML: ru.eldarkaa.dto.Company@d1e43ed -> 
ru.eldarkaa.dto.Department@6e55f58 -> ru.eldarkaa.dto.Company@d1e43ed]