java - 使用复合键休眠单向 OneToMany

Question

我想构建 Hibernate OneToMany 关系，其中 Parent 有一个复合主键，而 Child 有一个主键（休眠自动生成）。以下是我的工作示例代码：

class Parent{

    @EmbeddedId
    private ParentPk parentPk;

    @OneToMany( mappedBy="parent")
    private List<ChildType1>;

    @OneToMany( mappedBy="parent")
    private List<ChildType2>;

    @OneToMany( mappedBy="parent")
    private List<ChildType3>;

    //--setters and getters
}

@Embeddable
public class ParentPk {

    private Long parentId;

    private BigDecimal version;

    //..setters and getters
}

class ChildType1{
    @Id
    private Long childId;

    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumns({ @JoinColumn(name = "parentId"),
            @JoinColumn(name = "version") })
    private Parent parent;

    //..other fields and setters and getters
}

//--ChildType2 and ChildType3 like above

但是现在我想将上面的模型建模为 OneToMany 单向关系，即子级不应该引用父级（希望在子类中省略 Parent 实例）。可能吗？

Answer 1

一个示例方法：

@Entity
class Parent {
    @EmbeddedId
    private ParentPk parentPk;

    @OneToMany
    @JoinColumns({ 
        @JoinColumn(name = "parentId", referencedColumnName = "parentId"), 
        @JoinColumn(name = "version", referencedColumnName = "version")
    })
    private List<ChildType1> children1;

    // exactly the same annotations as for children1
    private List<ChildType2> children2;

    // exactly the same annotations as for children1
    private List<ChildType3> children3;

    //..other fields and setters and getters
}

@Entity
class ChildType1 {
    @Id
    private Long childId;

    //..other fields and setters and getters
}

//--ChildType2 and ChildType3 like above