[hibernate-dev] Eager fetch and duplicates of collection elements

[Gunnar Morling]

Hi,

I understand that $subject is a known source of confusion for people
when working with HQL/criteria queries and not applying something like
DistinctRootEntityResultTransformer.

I am seeing the same behaviour though when getting a root entity by id
and join-fetching two (nested) collections. That's my model:

    @Entity
    public class Parent {

        @Id @GeneratedValue
        private Long id;

        @OneToMany(cascade = CascadeType.ALL, fetch=FetchType.EAGER)
        @JoinColumn(name = "parent_id")
        private List<Child> children = new ArrayList<>();
    }

    @Entity
    public class Child {

        @Id @GeneratedValue
        private Long id;

        @ElementCollection(fetch=FetchType.EAGER)
        @JoinTable(name = "Child_Properties")
        @MapKeyColumn(name = "key")
        @Column(name = "value")
        private Map<String, String> properties = new HashMap<>();
    }

I am persisting a parent with one Child which has three "properties"
entries. Loading the Parent by id yields three elements in the
"children" list:

    Parent loaded = session.get( Parent.class, 123 );
    assert 1 == loaded.getConfigurations().size(); // <!-- Fails, it
contains the same Child three times

I don't think that's expected?

I can file an issue, but first wanted to make sure I am not missing
anything obvious.

Thanks,

--Gunnar