Details

    • Type: Sub-task Sub-task
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 2.0.0-M2
    • Component/s: None
    • Labels:
      None

      Description

      Regarding jpa 2.0 embeddable, suppose Entity A contains a collection of embeddables.
      The collection of embeddable is stored in a separate table. @CollectionTable can be used to specify the table name, etc. If the @CollectionTable is not used, a default table name is used (see spec, p 272 ).

      The embeddable may contain the relation to EntityB in the following scenarios:
      (1) If in the embeddable, there is:
      @ManyToOne
      private EnittyB entityB;

      then the relation from EntityA to EntityB is OneToMany,
      and the relation from EntityB to EntityA is ManyToOne (Spec 2.5):
      @ManyToOne
      private EntityA entityA;

      (2) If in the embeddable, there is:
      @OneToOne
      private EntityB;

      then the relation from EntityA to EntityB is OneToMany,
      and the relation from EntityB to EntityA is ManyToOne (Spec 2.5):
      @ManyToOne
      private EntityA entityA;

      (3) If in the embeddable, there is:
      @OneToOne(mappedBy = "entityB")
      private EntityB
      The relation from EntityA to EnityB is OneToMany,
      and the relation from EntityB to EntityA is ManyToOne:
      @ManyToOne
      private EntityA entityA;

      The relation to EntityB will be stored in the third table (the CollectionTable) so that it can be associated with the embeddable. However, we can not use "mappedBy" in the ManyToOne relation in EntityB. How to have bi-directional relation between EntityA and EntityB in these situations? Is it possible to have a bi-directional relation between these two entities when embeddable is involved as described above?

      In scenario (3), an explicit "mappedBy" is specified in the embeddable, so that the bi-directional relation between EntityA and EntityB will be stored in the EntityB table, but then how can we associate EntityB with the embeddable when EntityA is retrieved back as embeddable itself does not have identity?

      1. openjpa-782.patch
        20 kB
        Fay Wang
      2. openjpa-782-testcase.patch
        56 kB
        Fay Wang

        Issue Links

          Activity

          Hide
          Fay Wang added a comment -

          Another piece of information: in Spec 2.6: "The embeddable class must be on the owning side of such a relation and the relationship must be mapped by a foreign key mapping".

          Show
          Fay Wang added a comment - Another piece of information: in Spec 2.6: "The embeddable class must be on the owning side of such a relation and the relationship must be mapped by a foreign key mapping".
          Hide
          Fay Wang added a comment -

          The patch includes:
          (1) new JPA2.0 annotations: ElementCollection and CollectionTable.
          (2) fix of JIRA-777
          (3) fix to support the scenario when an entity contains a collection of embeddables, and the embeddable has a nested embeddable in it. Currently, openjpa only allows basic types and toOne relation in an embeddable element.

          Show
          Fay Wang added a comment - The patch includes: (1) new JPA2.0 annotations: ElementCollection and CollectionTable. (2) fix of JIRA-777 (3) fix to support the scenario when an entity contains a collection of embeddables, and the embeddable has a nested embeddable in it. Currently, openjpa only allows basic types and toOne relation in an embeddable element.
          Hide
          Fay Wang added a comment -

          ElementCollection/CollectionTable annotation and orm support for embeddables and basic types are committed to trunk r-724437 and r-725770. Test case for orm will be checked in later when the orm xml schema is finalized.

          Show
          Fay Wang added a comment - ElementCollection/CollectionTable annotation and orm support for embeddables and basic types are committed to trunk r-724437 and r-725770. Test case for orm will be checked in later when the orm xml schema is finalized.
          Hide
          Fay Wang added a comment -

          In this iteration, the following are supported:
          1) nested embeddables: spec 2.5
          2) collections of embeddables and basic types: spec 2.2, 2.6
          3) relationships within embeddables: spec 2.5, 10.1.22, 10.1.24, 10.1.25, 10.1.34
          4) @CollectionTable annotation and XML (Parser/Serializer): spec 10.1.7
          5) @ElementCollection annotation and XML (Parser/Serializer): spec 10.1.11

          Incmplete and pending issues:
          (1) 2.7.2
          (2) 10.1.35 (OrderBy for embeddable)
          (3) JIRA-793
          (4) processing/serialization for version 1 and version 2 of the ORM/PersistenceUnit XML Schema.

          Show
          Fay Wang added a comment - In this iteration, the following are supported: 1) nested embeddables: spec 2.5 2) collections of embeddables and basic types: spec 2.2, 2.6 3) relationships within embeddables: spec 2.5, 10.1.22, 10.1.24, 10.1.25, 10.1.34 4) @CollectionTable annotation and XML (Parser/Serializer): spec 10.1.7 5) @ElementCollection annotation and XML (Parser/Serializer): spec 10.1.11 Incmplete and pending issues: (1) 2.7.2 (2) 10.1.35 (OrderBy for embeddable) (3) JIRA-793 (4) processing/serialization for version 1 and version 2 of the ORM/PersistenceUnit XML Schema.
          Hide
          Fay Wang added a comment -

          Spec 2.5 Embeddable Classes (p 34):

          "Since instances of embeddable classes themselves have no persistent identity, the relationship from the referenced entity is to the entity that contains the embeddable instance(s) and not to the embeddable itself."

          Spec 10.1.26 ManyToOne Annotation (p. 310):

          "The ManyToOne annotation may be used within an embeddable class to specify a relationship from the embeddable class to an entity class."

          Spec 10.1.35 OneToOne Annotation (p.323):

          "The OneToOne annotation may be used within an embeddable class to specify a relationship from the embeddable class to an entity class. "

          Case (1):

          EntityA
          ======
          private Collection<EmbedA> embedAs;

          EmbedA:
          ========
          @ManyToOne
          EntityB entityB;

          The values for EntityA, EmbedA, EntityB can be:

          EntityA1 - EmbedA1 - EntityB1
          EmbedA2 - EntityB1
          EmbedA3 - EntityB2
          EmbedA4 - EntityB2

          The implied relation from EntityA to EntityB is therefore OneToMany. A bi-directional relation between EntityA and EntityB (spec p.40) suggests that the relation from EntityB to EntityA is ManyToOne.

          EntityB:
          =======
          @ManyToOne
          private EntityA entityA;

          Case(2):

          EntityA
          ======
          private Collection<EmbedA> embedAs;

          EmbedA:
          ========
          @OneToOne
          EntityB entityB;

          The values for EntityA, EmbedA, EntityB can be:

          EntityA1 - EmbedA1 - EntityB1
          EmbedA2 - EntityB2
          EmbedA3 - EntityB3
          EmbedA4 - EntityB4

          The implied relation from EntityA to EntityB is therefore OneToMany. A bi-directional relation between EntityA and EntityB (spec p.40) suggests that the relation from EntityB to EntityA is ManyToOne.

          EntityB:
          =======
          @ManyToOne
          private EntityA entityA;

          In both cases, EntityA should be the owning side (as it contains EmbedA). In order to specify bi-directional relation, the mappedBy annotation should be specified in EntityB, However, EntityB has ManyToOne relation, which disallows "mappedBy" to be specified. Therefore, IMO, it is not possible to specify bi-directional relation when a collection embeddables is involved.

          Show
          Fay Wang added a comment - Spec 2.5 Embeddable Classes (p 34): "Since instances of embeddable classes themselves have no persistent identity, the relationship from the referenced entity is to the entity that contains the embeddable instance(s) and not to the embeddable itself." Spec 10.1.26 ManyToOne Annotation (p. 310): "The ManyToOne annotation may be used within an embeddable class to specify a relationship from the embeddable class to an entity class." Spec 10.1.35 OneToOne Annotation (p.323): "The OneToOne annotation may be used within an embeddable class to specify a relationship from the embeddable class to an entity class. " Case (1): EntityA ====== private Collection<EmbedA> embedAs; EmbedA: ======== @ManyToOne EntityB entityB; The values for EntityA, EmbedA, EntityB can be: EntityA1 - EmbedA1 - EntityB1 EmbedA2 - EntityB1 EmbedA3 - EntityB2 EmbedA4 - EntityB2 The implied relation from EntityA to EntityB is therefore OneToMany. A bi-directional relation between EntityA and EntityB (spec p.40) suggests that the relation from EntityB to EntityA is ManyToOne. EntityB: ======= @ManyToOne private EntityA entityA; Case(2): EntityA ====== private Collection<EmbedA> embedAs; EmbedA: ======== @OneToOne EntityB entityB; The values for EntityA, EmbedA, EntityB can be: EntityA1 - EmbedA1 - EntityB1 EmbedA2 - EntityB2 EmbedA3 - EntityB3 EmbedA4 - EntityB4 The implied relation from EntityA to EntityB is therefore OneToMany. A bi-directional relation between EntityA and EntityB (spec p.40) suggests that the relation from EntityB to EntityA is ManyToOne. EntityB: ======= @ManyToOne private EntityA entityA; In both cases, EntityA should be the owning side (as it contains EmbedA). In order to specify bi-directional relation, the mappedBy annotation should be specified in EntityB, However, EntityB has ManyToOne relation, which disallows "mappedBy" to be specified. Therefore, IMO, it is not possible to specify bi-directional relation when a collection embeddables is involved.

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            • Assignee:
              Fay Wang
              Reporter:
              Fay Wang
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                Development