Trying to load the entities of a @OneToMany relation with the @Loader annotation and a @NamedNativeQuery causes a NullPointerException when the PersistentSet is accessed for the first time:

PersistentSet.iterator() line: 181

Example:

@Entity
@Table(name = "ROOT_ENTITY")
@NamedNativeQuery(name="loadChildEntities", query="select * from CHILD_ENTITY c where c.PARENT = ?", resultClass=ChildEntity.class)
public class RootEntity {
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "root_entity_seq")
@SequenceGenerator(name = "root_entity_seq", sequenceName = "ROOT_ENTITY_ID_SEQ", allocationSize = 1)
private long id;

@OneToMany(mappedBy = "rootEntity", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@Loader(namedQuery="loadChildEntities")
private Set<ChildEntity> childEntities = new HashSet<ChildEntity>(0);
...

And the ChildEntity:

@Entity
@Table(name = "CHILD_ENTITY")
public class ChildEntity {
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "child_entity_seq")
@SequenceGenerator(name = "child_entity_seq", sequenceName = "CHILD_ENTITY_ID_SEQ", allocationSize = 1)
private long id;

@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "PARENT")
private RootEntity rootEntity;
...

Example maven project attached to this issue.