BatchFetch IN fails to fetch eager reference when selecting non-root entity

[andilem]

EclipseLink version 4.0.2

When selecting a non-root entity (e.g. query.select(root.get(child))) and child has a @ManyToOne reference with @BatchFetch(value=IN), the references of the children are not fetched. They are just null, even with fetchType=EAGER.

There is a simple test case attached with

• three entity types with unidirectional (eager) many-to-one references (Record -> User -> Company)
• User -> Company reference has @BatchFetch(value=IN)
• query.select(query.from(Record.class).get("user"))
• em.createQuery(query).getResultList() returns users with company = null
• when removing @BatchFetch(value=IN), everything works as expected

eclipselink-batchfetch-selectnonroot.zip

[impacsl]

We have similar issues with OneToOne-references with three entities using BatchFetchType IN/JOIN/EXISTS:

Record - OneToMany / LAZY - Transaction - OneToOne / BatchFetch - Communication

In some cases the List of Transactions contains Communications that are null.

When removing the @BatchFetch it works as well as expected.

EclipseLink 4.0.2, but also other versions (4.0.1, 2.7.14)