The mapping [itemId] from the embedded ID class [class example.ItemInventoryCompositeKey] is an invalid mapping for this class

Support
#1

Hi,

It seems the problem still exist with the latest Cuba version. I tried to use composite key following the example mentioned in the start of this thread, I am getting the error:

> Caused by: Exception [EclipseLink-7298] (Eclipse Persistence Services - 2.7.3.6-cuba): org.eclipse.persistence.exceptions.ValidationException
> Exception Description: The mapping [itemId] from the embedded ID class [class example.ItemInventoryCompositeKey] is an invalid mapping for this class. An embeddable class that is used with an embedded ID specification (attribute [itemInventoryCompositeKey] from the source [class example.ItemInventory]) can only contain basic mappings. Either remove the non basic mapping or change the embedded ID specification on the source to be embedded.
> 	at org.eclipse.persistence.exceptions.ValidationException.invalidMappingForEmbeddedId(ValidationException.java:1312)
> 	at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.EmbeddedIdAccessor.addIdFieldsFromAccessors(EmbeddedIdAccessor.java:152)
> 	at org.eclipse.persistence.internal.jpa.metadata.accessors.mappings.EmbeddedIdAccessor.process(EmbeddedIdAccessor.java:195)
> 	at org.eclipse.persistence.internal.jpa.metadata.MetadataDescriptor.processMappingAccessors(MetadataDescriptor.java:1525)
> 	at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.ClassAccessor.processMappingAccessors(ClassAccessor.java:1658)
> 	at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.processMappingAccessors(EntityAccessor.java:1242)
> 	at org.eclipse.persistence.internal.jpa.metadata.accessors.classes.EntityAccessor.process(EntityAccessor.java:701)
> 	at org.eclipse.persistence.internal.jpa.metadata.MetadataProject.processStage2(MetadataProject.java:1879)
> 	at org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.processORMMetadata(MetadataProcessor.java:580)
> 	at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProcessor.processORMetadata(PersistenceUnitProcessor.java:629)
> 	at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy(EntityManagerSetupImpl.java:2001)
> 	... 6 more

Any idea how to solve this problem?

#3

Hi,
Unfortunately, there is no simple way to use association attributes in composite PK, as EclipseLink does not support it.

But you can work around the problem as follows:

Let’s suppose Entity_1 has a composite PK.
The PK is presented by KeyEntity (EmbeddableEntity). It was created by CUBA Studio and has a link to Entity_2.

  1. In the “KeyEntity” modify the link field: make it of basic type instead of @ManyToOne.
public class KeyEntity extends EmbeddableEntity {
...
    @Column(name = "ENTITY2LINK_ID")
    protected Integer entity2link; //Entity_2 has Integer Id
...
  1. Then in the Entity_1 create the property entity_2 mark it with @Transient and @MetaProperty, and define its get/set methods similar to following.
....
@EmbeddedId
protected KeyEntity id;

@Transient
@MetaProperty
protected Entity_2 entity_2;

 public Entity_2 getEntity_2() {
        if (entity_2 == null && id.getEntity2link() != null) {
            DataManager dm = AppBeans.get(DataManager.class);
            entity_2 = dm.load(LoadContext
                    .create(Entity_2.class)
                    .setId(id.getEntity2link()));
        }
        return entity_2;
    }

    public void setEntity_2(Entity_2 entity_2) {
        this.id.setEntity2link(entity_2.getId());
        this.entity_2 = entity_2;
    }

This should work.

Regards.

1 Like
#4

Hi,

Thanks for the suggestion.

With a composite key of 4 different objects that are not primitives (i.e. integer), the workaround starts to be quite complex (and ugly - please don’t take this personally).

I am trying to find a workaround from the data modelling perspective. If there are any ideas, please share.

Thanks,