Marko Bekhta ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiZTdmOTVlMGQ1... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16740?atlOrigin=eyJpIjoiZTdmOT... ) HHH-16740 ( https://hibernate.atlassian.net/browse/HHH-16740?atlOrigin=eyJpIjoiZTdmOT... ) Fetching an element collection on an entity with a composite id fails when batch size > 1 ( https://hibernate.atlassian.net/browse/HHH-16740?atlOrigin=eyJpIjoiZTdmOT... ) Issue Type: Bug Affects Versions: 6.2.4 Assignee: Unassigned Created: 02/Jun/2023 03:26 AM Priority: Major Reporter: Marko Bekhta ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) Having a model like: @Entity(name = "EntityA" ) public class EntityA { @EmbeddedId private EntityId id; @ElementCollection public Set<EmbeddableA> elementCollection = new HashSet<>(); } @Entity(name = "EntityB" ) public class EntityB { @Id private Long id; } @Embeddable public class EntityId implements Serializable { private String id1; @ManyToOne @MapsId private EntityB id2; } @Embeddable public class EmbeddableA { private String name; } Trying to access element collection: EntityA a = entityManager.find( EntityA.class, ENTITY_A_ID ); a.elementCollection.size(); Leads to: java.lang.NullPointerException at org.hibernate.sql.results.graph.entity.internal.BatchEntityInsideEmbeddableSelectFetchInitializer.getRootEmbeddablePropertyName(BatchEntityInsideEmbeddableSelectFetchInitializer.java:190) at org.hibernate.sql.results.graph.entity.internal.BatchEntityInsideEmbeddableSelectFetchInitializer.<init>(BatchEntityInsideEmbeddableSelectFetchInitializer.java:57) at org.hibernate.sql.results.graph.entity.internal.EntitySelectFetchInitializerBuilder.createInitializer(EntitySelectFetchInitializerBuilder.java:62) at org.hibernate.sql.results.graph.entity.internal.EntityFetchSelectImpl.buildEntitySelectFetchInitializer(EntityFetchSelectImpl.java:92) at org.hibernate.sql.results.graph.entity.internal.EntityFetchSelectImpl.lambda$createAssembler$0(EntityFetchSelectImpl.java:70) at org.hibernate.sql.results.internal.ResultsHelper$1.resolveInitializer(ResultsHelper.java:117) at org.hibernate.sql.results.graph.entity.internal.EntityFetchSelectImpl.createAssembler(EntityFetchSelectImpl.java:67) at org.hibernate.sql.results.graph.embeddable.AbstractEmbeddableInitializer.createAssemblers(AbstractEmbeddableInitializer.java:109) at org.hibernate.sql.results.graph.embeddable.AbstractEmbeddableInitializer.<init>(AbstractEmbeddableInitializer.java:75) at org.hibernate.sql.results.graph.embeddable.internal.EmbeddableResultInitializer.<init>(EmbeddableResultInitializer.java:22) at org.hibernate.sql.results.graph.embeddable.internal.EmbeddableForeignKeyResultImpl.lambda$createResultAssembler$0(EmbeddableForeignKeyResultImpl.java:104) at org.hibernate.sql.results.internal.ResultsHelper$1.resolveInitializer(ResultsHelper.java:117) at org.hibernate.sql.results.graph.embeddable.internal.EmbeddableForeignKeyResultImpl.createResultAssembler(EmbeddableForeignKeyResultImpl.java:99) at org.hibernate.sql.results.graph.collection.internal.CollectionDomainResult.lambda$createResultAssembler$0(CollectionDomainResult.java:100) at org.hibernate.sql.results.internal.ResultsHelper$1.resolveInitializer(ResultsHelper.java:117) at org.hibernate.sql.results.graph.collection.internal.CollectionDomainResult.createResultAssembler(CollectionDomainResult.java:96) at org.hibernate.sql.results.jdbc.internal.StandardJdbcValuesMapping.resolveAssemblers(StandardJdbcValuesMapping.java:53) at org.hibernate.sql.results.internal.ResultsHelper.createRowReader(ResultsHelper.java:76) at org.hibernate.sql.results.internal.ResultsHelper.createRowReader(ResultsHelper.java:62) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.doExecuteQuery(JdbcSelectExecutorStandardImpl.java:340) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.executeQuery(JdbcSelectExecutorStandardImpl.java:168) at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.list(JdbcSelectExecutorStandardImpl.java:93) at org.hibernate.sql.exec.spi.JdbcSelectExecutor.list(JdbcSelectExecutor.java:31) at org.hibernate.loader.ast.internal.CollectionLoaderSingleKey.load(CollectionLoaderSingleKey.java:115) at org.hibernate.loader.ast.internal.AbstractCollectionBatchLoader.load(AbstractCollectionBatchLoader.java:89) at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:679) at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:67) at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:127) at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:1703) at org.hibernate.collection.spi.AbstractPersistentCollection.lambda$initialize$3(AbstractPersistentCollection.java:615) at org.hibernate.collection.spi.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) at org.hibernate.collection.spi.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:613) at org.hibernate.collection.spi.AbstractPersistentCollection.read(AbstractPersistentCollection.java:136) at org.hibernate.collection.spi.AbstractPersistentCollection.lambda$readSize$0(AbstractPersistentCollection.java:162) at org.hibernate.collection.spi.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) at org.hibernate.collection.spi.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:148) at org.hibernate.collection.spi.PersistentSet.size(PersistentSet.java:151) at org.hibernate.orm.test.batch.CompositeIdAndElementCollectionBatchingTest.lambda$testSelect$1(CompositeIdAndElementCollectionBatchingTest.java:65) at org.hibernate.testing.orm.transaction.TransactionUtil.wrapInTransaction(TransactionUtil.java:49) at org.hibernate.testing.orm.transaction.TransactionUtil.inTransaction(TransactionUtil.java:24) at org.hibernate.testing.orm.junit.SessionFactoryExtension$SessionFactoryScopeImpl.inTransaction(SessionFactoryExtension.java:375) at org.hibernate.testing.orm.junit.SessionFactoryExtension$SessionFactoryScopeImpl.inTransaction(SessionFactoryExtension.java:352) at org.hibernate.orm.test.batch.CompositeIdAndElementCollectionBatchingTest.testSelect(CompositeIdAndElementCollectionBatchingTest.java:62) I will submit a reproducer. Most likely the same/similar problem as in ( https://hibernate.atlassian.net/browse/HHH-16286 ), but since there was no test case in the original issue, I’m opening this one. ( https://hibernate.atlassian.net/browse/HHH-16740#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16740#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100225- sha1:e03cc87 )