java - 关系实体用于在单个实体的对象之间创建层次结构

Question

我有一个可以有单亲和/或单子(monad)的组织实体。组织之间的层次结构需要有额外的列(例如关系类型)，因此我创建了一个实体OrganizationRelationship，用于父级和子级。我能够让子级使用 OneToMany 关联，但无法让父级工作(我猜应该使用 ManyToOne)。

我有一个可嵌入的主键，如下所示:

@Embeddable
public class OrganizationParentChildPk implements Serializable {

  @ManyToOne(cascade = CascadeType.ALL)
  public Organization parentOrganization;

  @ManyToOne(cascade = CascadeType.ALL)
  public Organization childOrganization;

}

然后是关系实体:

@Entity
@Table(name = "ORGANIZATION_LK")
@AssociationOverrides({
    @AssociationOverride(name = "pk.parentOrganization", joinColumns = @JoinColumn(name = "PARENT_ID")),
    @AssociationOverride(name = "pk.childOrganization", joinColumns = @JoinColumn(name = "CHILD_ID"))})
public class OrganizationRelationship implements Serializable {

  @EmbeddedId
  private OrganizationParentChildPk pk = null;

  @Column
  private String relationshipType = null;

}

最后，这是我的组织实体:

@Entity
@Table(name = "ORGANIZATION")
public class Organization extends Party {

  @Column(name = "NAME")
  private String name = null;

  // ???
  private OrganizationRelationship organizationParentRelationship = null;


  @OneToMany(mappedBy = "pk.parentOrganization", cascade = CascadeType.ALL,
      targetEntity = OrganizationRelationship.class)
  private Set<OrganizationRelationship> organizationChildRelationship = null;

}

如果可能的话，我想让父关系字段也使用相同的ORGANIZATION_LK表？

预先感谢您的帮助。

Answer 1

我设法使用以下注释让它工作:

  @OneToOne(mappedBy = "pk.childOrganization", cascade = CascadeType.ALL,
      targetEntity = OrganizationRelationship.class)
  private OrganizationRelationship organizationParentRelationship = null;