子级的JPA Hibernate MapsId

Question

我试图在JPA2.1中保存一个实体。我有三个表--MVCollection、MVCollectionVersion（它是MVCollection的版本）和MVBelomsCollection（它是属于一个版本的项）。MVCollection的主键是生成的序列号。当我生成一个带有版本（不包含任何项）的集合时，我使用@mapsid，生成的ID在子级中使用。然而，我似乎不能理解我如何能复制这与项目。

@Entity
public class MVCollection {

    @GeneratedValue(strategy = GenerationType.SEQUENCE, 
         generator = "MVCOLLECTION_SEQ")
    @SequenceGenerator(name = "MVCOLLECTION_SEQ", 
        sequenceName = "VMD.MVCOLLECTION_SEQ")
    @Id
    @Column(name = "MVCOLLECTIONID")
   private Long id;

MVCollectionVersion

@Entity
public class MVCollectionVersion {
    @EmbeddedId
    @AttributeOverrides({
        @AttributeOverride(name = "versionId", column = @Column(name = "MVCVSNID")) })

    private MVCollectionVersionId id;

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumns({
        @JoinColumn(name = "MVCOLLECTIONID", referencedColumnName = "MVCOLLECTIONID"),
     })
    @MapsId("mvCollectionId")
    private MVCollection mvCollection;

    @OneToMany(fetch = FetchType.LAZY, mappedBy="mvCollectionVersion", cascade={CascadeType.MERGE, CascadeType.PERSIST})
   private List<MVBelongsCollection> mvCollectionItems; 

MVCollectionID

@Embeddable
public class MVCollectionVersionId implements java.io.Serializable {

/**
 * 
 */
    private static final long serialVersionUID = 2551937096790427792L;
    private Long mvCollectionId;
    private Integer versionId;

MVbelongsCollection

@Entity
public class MVCollectionItems

    @EmbeddedId
    @AttributeOverrides({
        @AttributeOverride(name = "managedViewId", column = @Column(name = "MANAGEDVIEWID")),
        @AttributeOverride(name = "mvCollectionId", column = @Column(name = "MVCOLLECTIONID")),
        @AttributeOverride(name = "versionId", column = @Column(name = "MVCVSNID")) })

    private MVBelongsCollectionId id;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumns({
        @JoinColumn(name = "MVCOLLECTIONID", referencedColumnName = "MVCOLLECTIONID"),
        @JoinColumn(name = "MVCVSNID", referencedColumnName = "MVCVSNID") })
    private MVCollectionVersion mvCollectionVersion;

@Embeddable
public class MVBelongsCollectionId implements Serializable{


/**
 * 
 */
    private static final long serialVersionUID = 1L;

    @Column ( name = "MANAGEDVIEWID", nullable = false, precision = 38)
    private Long managedViewId;

    @Column ( name = "MVCOLLECTIONID", nullable = false, precision = 38)
    private Long mvCollectionId;

    @Column ( name = "MVCVSNID", nullable = false, precision = 38)
    private Integer versionId;

public class MVBelongsCollection {

/**
 * primary key
 */
    @EmbeddedId
    @AttributeOverrides({
        @AttributeOverride(name = "managedViewId", column = @Column(name = "MANAGEDVIEWID")),
        //@AttributeOverride(name = "mvCollectionId", column = @Column(name = "MVCOLLECTIONID")),
        @AttributeOverride(name = "versionId", column = @Column(name = "MVCVSNID")) })
    private MVBelongsCollectionId id;


/**
 * collection that this joins to.
 */
    @ManyToOne(fetch = FetchType.LAZY)
    @MapsId("mvCollectionId")
    @JoinColumns({
        @JoinColumn(name = "MVCOLLECTIONID", referencedColumnName = "MVCOLLECTIONID"),
        @JoinColumn(name = "MVCVSNID", referencedColumnName = "MVCVSNID") })
    private MVCollectionVersion mvCollectionVersion;

The type of the ID mapped by the relationship 'mvCollectionVersion' does not agree with the primary key class of the target entity.

我尝试将insertable=false和updatable=false添加到我的@JoinColumn、@AttributeOverride和基础ID类中，但仍然得到相同的错误。只有当@mapsid存在时才会发生这种情况。

我现在不知道如何让MVBelongsCollection使用生成的MVCollectionId，或者如何阻止eclipse和运行时错误。

如果有人能帮忙，我将不胜感激。提前致谢

Answer 1

我发现了自己的错误...

我需要在整个过程中使用相同的embeddedId。因此，MVBelongsCollectionId需要更改以包括父类的嵌入id：

@Embeddable
public class MVBelongsCollectionId implements Serializable{


    /**
    * 
    */
    private static final long serialVersionUID = 1L;

    @Embedded
    @AttributeOverrides( {
        @AttributeOverride(name = "mvCollectionId", column = @Column(name = "MVCOLLECTIONID", nullable = false, precision = 38, scale = 0)),
        @AttributeOverride(name = "versionId", column = @Column(name = "MVCVSNID", nullable = false, precision = 8, scale = 0)) 

    })
    MVCollectionVersionId collectionVersionId;

    @Column ( name = "MANAGEDVIEWID", nullable = false, precision = 38)
    private Long managedViewId;

   ....