Merge remote-tracking branch 'upstream5/master' into wip/6.0_merged_8

hibernate-core/src/main/java/org/hibernate/boot/MetadataSources.java

@@ -62,10 +62,10 @@ public class MetadataSources implements Serializable {
 
 	private XmlMappingBinderAccess xmlMappingBinderAccess;
 
-	private List<Binding> xmlBindings = new ArrayList<>();
+	private List<Binding> xmlBindings;
-	private LinkedHashSet<Class<?>> annotatedClasses = new LinkedHashSet<>();
+	private LinkedHashSet<Class<?>> annotatedClasses;
-	private LinkedHashSet<String> annotatedClassNames = new LinkedHashSet<>();
+	private LinkedHashSet<String> annotatedClassNames;
-	private LinkedHashSet<String> annotatedPackages = new LinkedHashSet<>();
+	private LinkedHashSet<String> annotatedPackages;
 
 	private Map<String,Class<?>> extraQueryImports;
 
@@ -81,14 +81,15 @@ public class MetadataSources implements Serializable {
 	public MetadataSources(ServiceRegistry serviceRegistry) {
 		// service registry really should be either BootstrapServiceRegistry or StandardServiceRegistry type...
 		if ( ! isExpectedServiceRegistryType( serviceRegistry ) ) {
-			LOG.debugf(
+			if ( LOG.isDebugEnabled() ) {
-					"Unexpected ServiceRegistry type [%s] encountered during building of MetadataSources; may cause " +
+				LOG.debugf(
-							"problems later attempting to construct MetadataBuilder",
+						"Unexpected ServiceRegistry type [%s] encountered during building of MetadataSources; may cause " +
-					serviceRegistry.getClass().getName()
+								"problems later attempting to construct MetadataBuilder",
-			);
+						serviceRegistry.getClass().getName()
+				);
+			}
 		}
 		this.serviceRegistry = serviceRegistry;
-		this.xmlMappingBinderAccess = new XmlMappingBinderAccess( serviceRegistry );
 	}
 
 	protected static boolean isExpectedServiceRegistryType(ServiceRegistry serviceRegistry) {
@@ -97,23 +98,26 @@ public class MetadataSources implements Serializable {
 	}
 
 	public XmlMappingBinderAccess getXmlMappingBinderAccess() {
+		if ( xmlMappingBinderAccess == null ) {
+			xmlMappingBinderAccess = new XmlMappingBinderAccess( serviceRegistry );
+		}
 		return xmlMappingBinderAccess;
 	}
 
 	public List<Binding> getXmlBindings() {
-		return xmlBindings;
+		return xmlBindings == null ? Collections.emptyList() : xmlBindings;
 	}
 
 	public Collection<String> getAnnotatedPackages() {
-		return annotatedPackages;
+		return annotatedPackages == null ? Collections.emptySet() : annotatedPackages;
 	}
 
 	public Collection<Class<?>> getAnnotatedClasses() {
-		return annotatedClasses;
+		return annotatedClasses == null ? Collections.emptySet() : annotatedClasses;
 	}
 
 	public Collection<String> getAnnotatedClassNames() {
-		return annotatedClassNames;
+		return annotatedClassNames == null ? Collections.emptySet() : annotatedClassNames;
 	}
 
 	public Map<String,Class<?>> getExtraQueryImports() {
@@ -201,6 +205,9 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining)
 	 */
 	public MetadataSources addAnnotatedClass(Class annotatedClass) {
+		if ( annotatedClasses == null ) {
+			annotatedClasses = new LinkedHashSet<>();
+		}
 		annotatedClasses.add( annotatedClass );
 		return this;
 	}
@@ -225,6 +232,9 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining)
 	 */
 	public MetadataSources addAnnotatedClassName(String annotatedClassName) {
+		if ( annotatedClassNames == null ) {
+			annotatedClassNames = new LinkedHashSet<>();
+		}
 		annotatedClassNames.add( annotatedClassName );
 		return this;
 	}
@@ -265,11 +275,17 @@ public class MetadataSources implements Serializable {
 			packageName = packageName.substring( 0, packageName.length() - 1 );
 		}
 
-		annotatedPackages.add( packageName );
+		addPackageInternal( packageName );
-
 		return this;
 	}
 
+	private void addPackageInternal(String packageName) {
+		if ( annotatedPackages == null ) {
+			annotatedPackages = new LinkedHashSet<>();
+		}
+		annotatedPackages.add( packageName );
+	}
+
 	/**
 	 * Read package-level metadata.
 	 *
@@ -278,7 +294,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining)
 	 */
 	public MetadataSources addPackage(Package packageRef) {
-		annotatedPackages.add( packageRef.getName() );
+		addPackageInternal( packageRef.getName() );
 		return this;
 	}
 
@@ -297,7 +313,9 @@ public class MetadataSources implements Serializable {
 		if ( entityClass == null ) {
 			throw new IllegalArgumentException( "The specified class cannot be null" );
 		}
-		LOG.debugf( "adding resource mappings from class convention : %s", entityClass.getName() );
+		if ( LOG.isDebugEnabled() ) {
+			LOG.debugf( "adding resource mappings from class convention : %s", entityClass.getName() );
+		}
 		final String mappingResourceName = entityClass.getName().replace( '.', '/' ) + ".hbm.xml";
 		addResource( mappingResourceName );
 		return this;
@@ -311,7 +329,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addResource(String name) {
-		xmlBindings.add( getXmlMappingBinderAccess().bind( name ) );
+		getXmlBindingsForWrite().add( getXmlMappingBinderAccess().bind( name ) );
 		return this;
 	}
 
@@ -337,7 +355,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addFile(File file) {
-		xmlBindings.add( getXmlMappingBinderAccess().bind( file ) );
+		getXmlBindingsForWrite().add( getXmlMappingBinderAccess().bind( file ) );
 		return this;
 	}
 
@@ -357,7 +375,7 @@ public class MetadataSources implements Serializable {
 	}
 
 	private void addCacheableFile(Origin origin, File file) {
-		xmlBindings.add( new CacheableFileXmlSource( origin, file, false ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
+		getXmlBindingsForWrite().add( new CacheableFileXmlSource( origin, file, false ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
 	}
 
 	/**
@@ -394,7 +412,7 @@ public class MetadataSources implements Serializable {
 	 */
 	public MetadataSources addCacheableFileStrictly(File file) throws SerializationException, FileNotFoundException {
 		final Origin origin = new Origin( SourceType.FILE, file.getAbsolutePath() );
-		xmlBindings.add( new CacheableFileXmlSource( origin, file, true ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
+		getXmlBindingsForWrite().add( new CacheableFileXmlSource( origin, file, true ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
 		return this;
 	}
 
@@ -406,7 +424,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addInputStream(InputStreamAccess xmlInputStreamAccess) {
-		xmlBindings.add( getXmlMappingBinderAccess().bind( xmlInputStreamAccess ) );
+		getXmlBindingsForWrite().add( getXmlMappingBinderAccess().bind( xmlInputStreamAccess ) );
 		return this;
 	}
 
@@ -418,7 +436,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addInputStream(InputStream xmlInputStream) {
-		xmlBindings.add( getXmlMappingBinderAccess().bind( xmlInputStream ) );
+		getXmlBindingsForWrite().add( getXmlMappingBinderAccess().bind( xmlInputStream ) );
 		return this;
 	}
 
@@ -430,7 +448,7 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addURL(URL url) {
-		xmlBindings.add( getXmlMappingBinderAccess().bind( url ) );
+		getXmlBindingsForWrite().add( getXmlMappingBinderAccess().bind( url ) );
 		return this;
 	}
 
@@ -446,7 +464,7 @@ public class MetadataSources implements Serializable {
 	@Deprecated
 	public MetadataSources addDocument(Document document) {
 		final Origin origin = new Origin( SourceType.DOM, Origin.UNKNOWN_FILE_PATH );
-		xmlBindings.add( new JaxpSourceXmlSource( origin, new DOMSource( document ) ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
+		getXmlBindingsForWrite().add( new JaxpSourceXmlSource( origin, new DOMSource( document ) ).doBind( getXmlMappingBinderAccess().getMappingBinder() ) );
 		return this;
 	}
 
@@ -460,17 +478,22 @@ public class MetadataSources implements Serializable {
 	 * @return this (for method chaining purposes)
 	 */
 	public MetadataSources addJar(File jar) {
-		LOG.debugf( "Seeking mapping documents in jar file : %s", jar.getName() );
+		if ( LOG.isDebugEnabled() ) {
+			LOG.debugf( "Seeking mapping documents in jar file : %s", jar.getName() );
+		}
 		final Origin origin = new Origin( SourceType.JAR, jar.getAbsolutePath() );
 		try {
 			JarFile jarFile = new JarFile( jar );
+			final boolean TRACE = LOG.isTraceEnabled();
 			try {
 				Enumeration jarEntries = jarFile.entries();
 				while ( jarEntries.hasMoreElements() ) {
 					final ZipEntry zipEntry = (ZipEntry) jarEntries.nextElement();
 					if ( zipEntry.getName().endsWith( ".hbm.xml" ) ) {
-						LOG.tracef( "found mapping document : %s", zipEntry.getName() );
+						if ( TRACE ) {
-						xmlBindings.add(
+							LOG.tracef( "found mapping document : %s", zipEntry.getName() );
+						}
+						getXmlBindingsForWrite().add(
 								new JarFileEntryXmlSource( origin, jarFile, zipEntry ).doBind( getXmlMappingBinderAccess().getMappingBinder() )
 						);
 					}
@@ -490,6 +513,13 @@ public class MetadataSources implements Serializable {
 		return this;
 	}
 
+	private <Binding> List getXmlBindingsForWrite() {
+		if ( xmlBindings == null ) {
+			xmlBindings = new ArrayList<>();
+		}
+		return xmlBindings;
+	}
+
 	/**
 	 * Read all mapping documents from a directory tree.
 	 * <p/>

hibernate-core/src/main/java/org/hibernate/cfg/annotations/MapBinder.java

@@ -437,7 +437,7 @@ public class MapBinder extends CollectionBinder {
 				referencedEntityColumns = referencedProperty.getColumnIterator();
 			}
 			fromAndWhere = getFromAndWhereFormula(
-					associatedClass.getTable().getName(),
+					associatedClass.getTable().getQualifiedTableName().toString(),
 					element.getColumnIterator(),
 					referencedEntityColumns
 			);

hibernate-core/src/main/java/org/hibernate/context/internal/ThreadLocalSessionContext.java

@@ -332,6 +332,7 @@ public class ThreadLocalSessionContext extends AbstractCurrentSessionContext {
 							|| "getTransaction".equals( methodName )
 							|| "isTransactionInProgress".equals( methodName )
 							|| "setFlushMode".equals( methodName )
+							|| "setHibernateFlushMode".equals( methodName )
 							|| "getFactory".equals( methodName )
 							|| "getSessionFactory".equals( methodName )
 							|| "getTenantIdentifier".equals( methodName ) ) {

hibernate-core/src/main/java/org/hibernate/engine/spi/SharedSessionContractImplementor.java

@@ -260,15 +260,6 @@ public interface SharedSessionContractImplementor
 	Object internalLoad(String entityName, Serializable id, boolean eager, boolean nullable)
 			throws HibernateException;
 
-	default Object internalLoad(
-			String entityName,
-			Serializable id,
-			boolean eager,
-			boolean nullable,
-			Boolean unwrapProxy) throws HibernateException {
-		return internalLoad( entityName, id, eager, nullable );
-	}
-
 	/**
 	 * Load an instance immediately. This method is only called when lazily initializing a proxy.
 	 * Do not return the proxy.

hibernate-core/src/main/java/org/hibernate/event/internal/DefaultLoadEventListener.java

@@ -299,15 +299,18 @@ public class DefaultLoadEventListener implements LoadEventListener {
 					return createProxy( event, persister, keyToLoad, persistenceContext );
 				}
 			}
+			if ( !entityMetamodel.hasSubclasses() ) {
+				if ( keyToLoad.isBatchLoadable() ) {
+					// Add a batch-fetch entry into the queue for this entity
+					persistenceContext.getBatchFetchQueue().addBatchLoadableEntityKey( keyToLoad );
+				}
 
-			if ( keyToLoad.isBatchLoadable() ) {
+				// This is the crux of HHH-11147
-				// Add a batch-fetch entry into the queue for this entity
+				// create the (uninitialized) entity instance - has only id set
-				persistenceContext.getBatchFetchQueue().addBatchLoadableEntityKey( keyToLoad );
+				return persister.getBytecodeEnhancementMetadata().createEnhancedProxy( keyToLoad, true, session );
 			}
-
+			// If we get here, then the entity class has subclasses and there is no HibernateProxy factory.
-			// This is the crux of HHH-11147
+			// The entity will get loaded below.
-			// create the (uninitialized) entity instance - has only id set
-			return persister.getBytecodeEnhancementMetadata().createEnhancedProxy( keyToLoad, true, session );
 		}
 		else {
 			if ( persister.hasProxy() ) {

hibernate-core/src/main/java/org/hibernate/internal/SessionImpl.java

@@ -975,18 +975,7 @@ public final class SessionImpl
 			String entityName,
 			Serializable id,
 			boolean eager,
-			boolean nullable) throws HibernateException {
+			boolean nullable) {
-		return internalLoad( entityName, id, eager, nullable, null );
-
-	}
-
-	@Override
-	public final Object internalLoad(
-			String entityName,
-			Serializable id,
-			boolean eager,
-			boolean nullable,
-			Boolean unwrapProxy) {
 		final EffectiveEntityGraph effectiveEntityGraph = getLoadQueryInfluencers().getEffectiveEntityGraph();
 		final GraphSemantic semantic = effectiveEntityGraph.getSemantic();
 		final RootGraphImplementor<?> graph = effectiveEntityGraph.getGraph();

hibernate-core/src/main/java/org/hibernate/internal/StatelessSessionImpl.java

@@ -298,23 +298,48 @@ public class StatelessSessionImpl extends AbstractSharedSessionContract implemen
 			final BytecodeEnhancementMetadata bytecodeEnhancementMetadata = entityMetamodel.getBytecodeEnhancementMetadata();
 			if ( allowBytecodeProxy && bytecodeEnhancementMetadata.isEnhancedForLazyLoading() ) {
 
-				// we cannot use bytecode proxy for entities with subclasses
+				// if the entity defines a HibernateProxy factory, see if there is an
-				if ( !entityMetamodel.hasSubclasses() ) {
+				// existing proxy associated with the PC - and if so, use it
+				if ( persister.getEntityMetamodel().getTuplizer().getProxyFactory() != null ) {
+					final PersistenceContext persistenceContext = getPersistenceContext();
+					final Object proxy = persistenceContext.getProxy( entityKey );
+
+					if ( proxy != null ) {
+						if ( LOG.isTraceEnabled() ) {
+							LOG.trace( "Entity proxy found in session cache" );
+						}
+						if ( LOG.isDebugEnabled() && ( (HibernateProxy) proxy ).getHibernateLazyInitializer().isUnwrap() ) {
+							LOG.debug( "Ignoring NO_PROXY to honor laziness" );
+						}
+
+						return persistenceContext.narrowProxy( proxy, persister, entityKey, null );
+					}
+
+					// specialized handling for entities with subclasses with a HibernateProxy factory
+					if ( entityMetamodel.hasSubclasses() ) {
+						// entities with subclasses that define a ProxyFactory can create
+						// a HibernateProxy.
+						LOG.debugf( "Creating a HibernateProxy for to-one association with subclasses to honor laziness" );
+						return createProxy( entityKey );
+					}
 					return bytecodeEnhancementMetadata.createEnhancedProxy( entityKey, false, this );
 				}
-			}
+				else if ( !entityMetamodel.hasSubclasses() ) {
-
+					return bytecodeEnhancementMetadata.createEnhancedProxy( entityKey, false, this );
-			// we could not use bytecode proxy, check to see if we can use HibernateProxy
-			if ( persister.hasProxy() ) {
-				final PersistenceContext persistenceContext = getPersistenceContext();
-				final Object existingProxy = persistenceContext.getProxy( entityKey );
-				if ( existingProxy != null ) {
-					return persistenceContext.narrowProxy( existingProxy, persister, entityKey, null );
 				}
-				else {
+				// If we get here, then the entity class has subclasses and there is no HibernateProxy factory.
-					final Object proxy = persister.createProxy( id, this );
+				// The entity will get loaded below.
-					persistenceContext.addProxy( entityKey, proxy );
+			}
-					return proxy;
+			else {
+				if ( persister.hasProxy() ) {
+					final PersistenceContext persistenceContext = getPersistenceContext();
+					final Object existingProxy = persistenceContext.getProxy( entityKey );
+					if ( existingProxy != null ) {
+						return persistenceContext.narrowProxy( existingProxy, persister, entityKey, null );
+					}
+					else {
+						return createProxy( entityKey );
+					}
 				}
 			}
 		}
@@ -323,6 +348,12 @@ public class StatelessSessionImpl extends AbstractSharedSessionContract implemen
 		return get( entityName, id );
 	}
 
+	private Object createProxy(EntityKey entityKey) {
+		final Object proxy = entityKey.getPersister().createProxy( entityKey.getIdentifier(), this );
+		getPersistenceContext().addProxy( entityKey, proxy );
+		return proxy;
+	}
+
 	@Override
 	public boolean isAutoCloseSessionEnabled() {
 		return getFactory().getSessionFactoryOptions().isAutoCloseSessionEnabled();

hibernate-core/src/main/java/org/hibernate/loader/Loader.java

@@ -1733,16 +1733,21 @@ public abstract class Loader {
 		// see if the entity defines reference caching, and if so use the cached reference (if one).
 		if ( session.getCacheMode().isGetEnabled() && persister.canUseReferenceCacheEntries() ) {
 			final EntityDataAccess cache = persister.getCacheAccessStrategy();
-			final Object ck = cache.generateCacheKey(
+			if ( cache != null ) {
-					key.getIdentifier(),
+				final Object ck = cache.generateCacheKey(
-					persister,
+						key.getIdentifier(),
-					session.getFactory(),
+						persister,
-					session.getTenantIdentifier()
+						session.getFactory(),
+						session.getTenantIdentifier()
+				);
+				final Object cachedEntry = CacheHelper.fromSharedCache( session, ck, cache );
+				if ( cachedEntry != null ) {
+					CacheEntry entry = (CacheEntry) persister.getCacheEntryStructure().destructure(
+							cachedEntry,
+							factory
 					);
-			final Object cachedEntry = CacheHelper.fromSharedCache( session, ck, cache );
+					return ( (ReferenceCacheEntryImpl) entry ).getReference();
-			if ( cachedEntry != null ) {
+				}
-				CacheEntry entry = (CacheEntry) persister.getCacheEntryStructure().destructure( cachedEntry, factory );
-				return ( (ReferenceCacheEntryImpl) entry ).getReference();
 			}
 		}
 

hibernate-core/src/main/java/org/hibernate/type/EntityType.java

@@ -655,8 +655,7 @@ public abstract class EntityType extends AbstractType implements AssociationType
 				getAssociatedEntityName(),
 				id,
 				eager,
-				isNullable(),
+				isNullable()
-				unwrapProxy
 		);
 
 		if ( proxyOrEntity instanceof HibernateProxy ) {

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/QueryScrollingWithInheritanceTest.java

@@ -0,0 +1,306 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy;
+
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+import org.hibernate.Hibernate;
+import org.hibernate.ScrollMode;
+import org.hibernate.ScrollableResults;
+import org.hibernate.Session;
+import org.hibernate.StatelessSession;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.dialect.DB2Dialect;
+import org.hibernate.query.Query;
+import org.hibernate.stat.spi.StatisticsImplementor;
+
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author Andrea Boriero
+ */
+@RunWith(BytecodeEnhancerRunner.class)
+public class QueryScrollingWithInheritanceTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( EmployeeParent.class );
+		sources.addAnnotatedClass( Employee.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void testScrollableWithStatelessSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final StatelessSession statelessSession = sessionFactory().openStatelessSession();
+
+		try {
+			statelessSession.beginTransaction();
+			Query<Employee> query = statelessSession.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( false ) );
+						assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( false ) );
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			statelessSession.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( statelessSession.getTransaction().isActive() ) {
+				statelessSession.getTransaction().rollback();
+			}
+			statelessSession.close();
+		}
+	}
+
+	@Test
+	public void testScrollableWithSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final Session session = sessionFactory().openSession();
+
+		try {
+			session.beginTransaction();
+			Query<Employee> query = session.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( false ) );
+						assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( false ) );
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			session.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( session.getTransaction().isActive() ) {
+				session.getTransaction().rollback();
+			}
+			session.close();
+		}
+	}
+
+	@Before
+	public void prepareTestData() {
+		inTransaction(
+				session -> {
+					Employee e1 = new Employee( "ENG1" );
+					Employee e2 = new Employee( "ENG2" );
+					OtherEntity other1 = new OtherEntity( "test1" );
+					OtherEntity other2 = new OtherEntity( "test2" );
+					e1.getOtherEntities().add( other1 );
+					e1.getOtherEntities().add( other2 );
+					e1.getParentOtherEntities().add( other1 );
+					e1.getParentOtherEntities().add( other2 );
+					other1.employee = e1;
+					other2.employee = e1;
+					other1.employeeParent = e1;
+					other2.employeeParent = e2;
+					session.persist( other1 );
+					session.persist( other2 );
+					session.persist( e1 );
+					session.persist( e2 );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Employee" ).executeUpdate();
+					session.createQuery( "delete from EmployeeParent" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "EmployeeParent")
+	@Table(name = "EmployeeParent")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	public static abstract class EmployeeParent {
+
+		@Id
+		private String dept;
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employeeParent", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> parentOtherEntities = new HashSet<>();
+
+		public Set<OtherEntity> getParentOtherEntities() {
+			if ( parentOtherEntities == null ) {
+				parentOtherEntities = new LinkedHashSet();
+			}
+			return parentOtherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pParentOtherEntites) {
+			parentOtherEntities = pParentOtherEntites;
+		}
+
+		public String getDept() {
+			return dept;
+		}
+
+		protected void setDept(String dept) {
+			this.dept = dept;
+		}
+
+	}
+
+	@Entity(name = "Employee")
+	@Table(name = "Employee")
+	public static class Employee extends EmployeeParent {
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employee", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> otherEntities = new HashSet<>();
+
+		public Employee(String dept) {
+			this();
+			setDept( dept );
+		}
+
+		protected Employee() {
+			// this form used by Hibernate
+		}
+
+		public Set<OtherEntity> getOtherEntities() {
+			if ( otherEntities == null ) {
+				otherEntities = new LinkedHashSet();
+			}
+			return otherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pOtherEntites) {
+			otherEntities = pOtherEntites;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		@JoinColumn(name = "Employee_Id")
+		protected Employee employee = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		@JoinColumn(name = "EmployeeParent_Id")
+		protected EmployeeParent employeeParent = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/LazyToOnesNoProxyFactoryWithSubclassesStatefulTest.java

@@ -0,0 +1,476 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy.proxy;
+
+import java.io.Serializable;
+import java.util.Map;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+import org.hibernate.EntityMode;
+import org.hibernate.EntityNameResolver;
+import org.hibernate.Hibernate;
+import org.hibernate.HibernateException;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.annotations.Tuplizer;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.mapping.PersistentClass;
+import org.hibernate.property.access.spi.Getter;
+import org.hibernate.proxy.HibernateProxy;
+import org.hibernate.proxy.ProxyFactory;
+import org.hibernate.stat.Statistics;
+import org.hibernate.tuple.entity.EntityMetamodel;
+import org.hibernate.tuple.entity.EntityTuplizer;
+import org.hibernate.tuple.entity.PojoEntityTuplizer;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Gail Badner
+ */
+@TestForIssue( jiraKey = "HHH-13640" )
+@RunWith(BytecodeEnhancerRunner.class)
+public class LazyToOnesNoProxyFactoryWithSubclassesStatefulTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+		ssrb.applySetting( AvailableSettings.ALLOW_ENHANCEMENT_AS_PROXY, "true" );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( Animal.class );
+		sources.addAnnotatedClass( Primate.class );
+		sources.addAnnotatedClass( Human.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+	
+	@Test
+	public void testNewEnhancedProxyAssociation() {
+		inTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+
+					session.persist( human );
+					session.persist( otherEntity );
+				}
+		);
+
+		inSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@Test
+	public void testExistingInitializedAssociationLeafSubclass() {
+		inTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					otherEntity.primate = human;
+					otherEntity.human = human;
+					session.persist( human );
+					session.persist( otherEntity );
+				}
+		);
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		inSession(
+				session -> {
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.animal ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "primate" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.primate ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.primate ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertSame( otherEntity.human, otherEntity.animal );
+					assertSame( otherEntity.human, otherEntity.primate );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+				}
+		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+	}
+
+	@Test
+	public void testExistingEnhancedProxyAssociationLeafSubclassOnly() {
+		inTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+					otherEntity.otherHuman = human;
+					session.persist( human );
+					session.persist( otherEntity );
+				}
+		);
+
+		inSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertNull( otherEntity.animal );
+					assertNull( otherEntity.primate );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "otherHuman" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.otherHuman ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.otherHuman ) );
+					assertSame( otherEntity.human, otherEntity.otherHuman );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Human" ).executeUpdate();
+					session.createQuery( "delete from Primate" ).executeUpdate();
+					session.createQuery( "delete from Animal" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "Animal")
+	@Table(name = "Animal")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	@Tuplizer(impl=NoProxyFactoryPojoEntityTuplizer.class)
+	public static abstract class Animal {
+
+		@Id
+		private String name;
+
+		private int age;
+
+		public String getName() {
+			return name;
+		}
+
+		protected void setName(String name) {
+			this.name = name;
+		}
+
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
+	}
+
+	@Entity(name = "Primate")
+	@Table(name = "Primate")
+	public static class Primate extends Animal {
+
+		public Primate(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Primate() {
+			// this form used by Hibernate
+		}
+	}
+
+	@Entity(name = "Human")
+	@Table(name = "Human")
+	public static class Human extends Primate {
+
+		private String sex;
+
+		public Human(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Human() {
+			// this form used by Hibernate
+		}
+
+		public String getSex() {
+			return sex;
+		}
+
+		public void setSex(String sex) {
+			this.sex = sex;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Animal animal = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Primate primate = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human human = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human otherHuman = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+
+		public Human getHuman() {
+			return human;
+		}
+
+		public void setHuman(Human human) {
+			this.human = human;
+		}
+	}
+
+	public static class NoProxyFactoryPojoEntityTuplizer implements EntityTuplizer {
+
+		private final PojoEntityTuplizer pojoEntityTuplizer;
+
+		public NoProxyFactoryPojoEntityTuplizer(EntityMetamodel entityMetamodel, PersistentClass mappedEntity) {
+			pojoEntityTuplizer = new PojoEntityTuplizer( entityMetamodel, mappedEntity );
+		}
+
+		@Override
+		public EntityMode getEntityMode() {
+			return pojoEntityTuplizer.getEntityMode();
+		}
+
+		@Override
+		public Object instantiate(Serializable id) throws HibernateException {
+			return pojoEntityTuplizer.instantiate( id );
+		}
+
+		@Override
+		public Object instantiate(Serializable id, SharedSessionContractImplementor session) {
+			return pojoEntityTuplizer.instantiate( id, session );
+
+		}
+
+		@Override
+		public Serializable getIdentifier(Object entity) throws HibernateException {
+			return pojoEntityTuplizer.getIdentifier( entity );
+		}
+
+		@Override
+		public Serializable getIdentifier(Object entity, SharedSessionContractImplementor session) {
+			return pojoEntityTuplizer.getIdentifier( entity, session );
+		}
+
+		@Override
+		public void setIdentifier(Object entity, Serializable id) throws HibernateException {
+			pojoEntityTuplizer.setIdentifier( entity, id );
+		}
+
+		@Override
+		public void setIdentifier(Object entity, Serializable id, SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.setIdentifier( entity, id, session );
+		}
+
+		@Override
+		public void resetIdentifier(Object entity, Serializable currentId, Object currentVersion) {
+			pojoEntityTuplizer.resetIdentifier( entity, currentId, currentVersion );
+		}
+
+		@Override
+		public void resetIdentifier(
+				Object entity,
+				Serializable currentId,
+				Object currentVersion,
+				SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.resetIdentifier( entity, currentId, currentVersion, session );
+		}
+
+		@Override
+		public Object getVersion(Object entity) throws HibernateException {
+			return pojoEntityTuplizer.getVersion( entity );
+		}
+
+		@Override
+		public void setPropertyValue(Object entity, int i, Object value) throws HibernateException {
+			pojoEntityTuplizer. setPropertyValue( entity, i, value );
+		}
+
+		@Override
+		public void setPropertyValue(Object entity, String propertyName, Object value) throws HibernateException {
+			pojoEntityTuplizer.setPropertyValue( entity, propertyName, value );
+		}
+
+		@Override
+		public Object[] getPropertyValuesToInsert(
+				Object entity,
+				Map mergeMap,
+				SharedSessionContractImplementor session) throws HibernateException {
+			return pojoEntityTuplizer.getPropertyValuesToInsert( entity, mergeMap, session );
+		}
+
+		@Override
+		public Object getPropertyValue(Object entity, String propertyName) throws HibernateException {
+			return pojoEntityTuplizer.getPropertyValue( entity, propertyName );
+		}
+
+		@Override
+		public void afterInitialize(Object entity, SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.afterInitialize( entity, session );
+
+		}
+
+		@Override
+		public boolean hasProxy() {
+			return pojoEntityTuplizer.hasProxy();
+		}
+
+		@Override
+		public Object createProxy(Serializable id, SharedSessionContractImplementor session) throws HibernateException {
+			return pojoEntityTuplizer.createProxy( id, session );
+		}
+
+		@Override
+		public boolean isLifecycleImplementor() {
+			return pojoEntityTuplizer.isLifecycleImplementor();
+		}
+
+		@Override
+		public Class getConcreteProxyClass() {
+			return pojoEntityTuplizer.getConcreteProxyClass();
+		}
+
+		@Override
+		public EntityNameResolver[] getEntityNameResolvers() {
+			return pojoEntityTuplizer.getEntityNameResolvers();
+		}
+
+		@Override
+		public String determineConcreteSubclassEntityName(
+				Object entityInstance, SessionFactoryImplementor factory) {
+			return pojoEntityTuplizer.determineConcreteSubclassEntityName( entityInstance, factory );
+		}
+
+		@Override
+		public Getter getIdentifierGetter() {
+			return pojoEntityTuplizer.getIdentifierGetter();
+		}
+
+		@Override
+		public Getter getVersionGetter() {
+			return pojoEntityTuplizer.getVersionGetter();
+		}
+
+		@Override
+		public ProxyFactory getProxyFactory() {
+			return null;
+		}
+
+		@Override
+		public Object[] getPropertyValues(Object entity) {
+			return pojoEntityTuplizer.getPropertyValues( entity );
+		}
+
+		@Override
+		public void setPropertyValues(Object entity, Object[] values) {
+			pojoEntityTuplizer.setPropertyValues( entity, values );
+		}
+
+		@Override
+		public Object getPropertyValue(Object entity, int i) {
+			return pojoEntityTuplizer.getPropertyValue( entity, i );
+		}
+
+		@Override
+		public Object instantiate() {
+			return pojoEntityTuplizer.instantiate();
+		}
+
+		@Override
+		public boolean isInstance(Object object) {
+			return pojoEntityTuplizer.isInstance( object );
+		}
+
+		@Override
+		public Class getMappedClass() {
+			return pojoEntityTuplizer.getMappedClass();
+		}
+
+		@Override
+		public Getter getGetter(int i) {
+			return pojoEntityTuplizer.getGetter( i );
+		}
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/LazyToOnesNoProxyFactoryWithSubclassesStatelessTest.java

@@ -0,0 +1,476 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy.proxy;
+
+import java.io.Serializable;
+import java.util.Map;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+import org.hibernate.EntityMode;
+import org.hibernate.EntityNameResolver;
+import org.hibernate.Hibernate;
+import org.hibernate.HibernateException;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.annotations.Tuplizer;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.mapping.PersistentClass;
+import org.hibernate.property.access.spi.Getter;
+import org.hibernate.proxy.HibernateProxy;
+import org.hibernate.proxy.ProxyFactory;
+import org.hibernate.stat.Statistics;
+import org.hibernate.tuple.entity.EntityMetamodel;
+import org.hibernate.tuple.entity.EntityTuplizer;
+import org.hibernate.tuple.entity.PojoEntityTuplizer;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Gail Badner
+ */
+@TestForIssue( jiraKey = "HHH-13640" )
+@RunWith(BytecodeEnhancerRunner.class)
+public class LazyToOnesNoProxyFactoryWithSubclassesStatelessTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+		ssrb.applySetting( AvailableSettings.ALLOW_ENHANCEMENT_AS_PROXY, "true" );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( Animal.class );
+		sources.addAnnotatedClass( Primate.class );
+		sources.addAnnotatedClass( Human.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void testNewEnhancedProxyAssociation() {
+		inStatelessTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@Test
+	public void testExistingInitializedAssociationLeafSubclass() {
+		inStatelessSession(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					otherEntity.primate = human;
+					otherEntity.human = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		inStatelessSession(
+				session -> {
+
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.animal ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "primate" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.primate ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.primate ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertTrue( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertSame( otherEntity.human, otherEntity.animal );
+					assertSame( otherEntity.human, otherEntity.primate );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+				}
+		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+	}
+
+	@Test
+	public void testExistingEnhancedProxyAssociationLeafSubclassOnly() {
+		inStatelessSession(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+					otherEntity.otherHuman = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertNull( otherEntity.animal );
+					assertNull( otherEntity.primate );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "otherHuman" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.otherHuman ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.otherHuman ) );
+					assertSame( otherEntity.human, otherEntity.otherHuman );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Human" ).executeUpdate();
+					session.createQuery( "delete from Primate" ).executeUpdate();
+					session.createQuery( "delete from Animal" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "Animal")
+	@Table(name = "Animal")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	@Tuplizer(impl=NoProxyFactoryPojoEntityTuplizer.class)
+	public static abstract class Animal {
+
+		@Id
+		private String name;
+
+		private int age;
+
+		public String getName() {
+			return name;
+		}
+
+		protected void setName(String name) {
+			this.name = name;
+		}
+
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
+	}
+
+	@Entity(name = "Primate")
+	@Table(name = "Primate")
+	public static class Primate extends Animal {
+
+		public Primate(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Primate() {
+			// this form used by Hibernate
+		}
+	}
+
+	@Entity(name = "Human")
+	@Table(name = "Human")
+	public static class Human extends Primate {
+
+		private String sex;
+
+		public Human(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Human() {
+			// this form used by Hibernate
+		}
+
+		public String getSex() {
+			return sex;
+		}
+
+		public void setSex(String sex) {
+			this.sex = sex;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Animal animal = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Primate primate = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human human = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human otherHuman = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+
+		public Human getHuman() {
+			return human;
+		}
+
+		public void setHuman(Human human) {
+			this.human = human;
+		}
+	}
+
+	public static class NoProxyFactoryPojoEntityTuplizer implements EntityTuplizer {
+
+		private final PojoEntityTuplizer pojoEntityTuplizer;
+
+		public NoProxyFactoryPojoEntityTuplizer(EntityMetamodel entityMetamodel, PersistentClass mappedEntity) {
+			pojoEntityTuplizer = new PojoEntityTuplizer( entityMetamodel, mappedEntity );
+		}
+
+		@Override
+		public EntityMode getEntityMode() {
+			return pojoEntityTuplizer.getEntityMode();
+		}
+
+		@Override
+		public Object instantiate(Serializable id) throws HibernateException {
+			return pojoEntityTuplizer.instantiate( id );
+		}
+
+		@Override
+		public Object instantiate(Serializable id, SharedSessionContractImplementor session) {
+			return pojoEntityTuplizer.instantiate( id, session );
+
+		}
+
+		@Override
+		public Serializable getIdentifier(Object entity) throws HibernateException {
+			return pojoEntityTuplizer.getIdentifier( entity );
+		}
+
+		@Override
+		public Serializable getIdentifier(Object entity, SharedSessionContractImplementor session) {
+			return pojoEntityTuplizer.getIdentifier( entity, session );
+		}
+
+		@Override
+		public void setIdentifier(Object entity, Serializable id) throws HibernateException {
+			pojoEntityTuplizer.setIdentifier( entity, id );
+		}
+
+		@Override
+		public void setIdentifier(Object entity, Serializable id, SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.setIdentifier( entity, id, session );
+		}
+
+		@Override
+		public void resetIdentifier(Object entity, Serializable currentId, Object currentVersion) {
+			pojoEntityTuplizer.resetIdentifier( entity, currentId, currentVersion );
+		}
+
+		@Override
+		public void resetIdentifier(
+				Object entity,
+				Serializable currentId,
+				Object currentVersion,
+				SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.resetIdentifier( entity, currentId, currentVersion, session );
+		}
+
+		@Override
+		public Object getVersion(Object entity) throws HibernateException {
+			return pojoEntityTuplizer.getVersion( entity );
+		}
+
+		@Override
+		public void setPropertyValue(Object entity, int i, Object value) throws HibernateException {
+			pojoEntityTuplizer. setPropertyValue( entity, i, value );
+		}
+
+		@Override
+		public void setPropertyValue(Object entity, String propertyName, Object value) throws HibernateException {
+			pojoEntityTuplizer.setPropertyValue( entity, propertyName, value );
+		}
+
+		@Override
+		public Object[] getPropertyValuesToInsert(
+				Object entity,
+				Map mergeMap,
+				SharedSessionContractImplementor session) throws HibernateException {
+			return pojoEntityTuplizer.getPropertyValuesToInsert( entity, mergeMap, session );
+		}
+
+		@Override
+		public Object getPropertyValue(Object entity, String propertyName) throws HibernateException {
+			return pojoEntityTuplizer.getPropertyValue( entity, propertyName );
+		}
+
+		@Override
+		public void afterInitialize(Object entity, SharedSessionContractImplementor session) {
+			pojoEntityTuplizer.afterInitialize( entity, session );
+
+		}
+
+		@Override
+		public boolean hasProxy() {
+			return pojoEntityTuplizer.hasProxy();
+		}
+
+		@Override
+		public Object createProxy(Serializable id, SharedSessionContractImplementor session) throws HibernateException {
+			return pojoEntityTuplizer.createProxy( id, session );
+		}
+
+		@Override
+		public boolean isLifecycleImplementor() {
+			return pojoEntityTuplizer.isLifecycleImplementor();
+		}
+
+		@Override
+		public Class getConcreteProxyClass() {
+			return pojoEntityTuplizer.getConcreteProxyClass();
+		}
+
+		@Override
+		public EntityNameResolver[] getEntityNameResolvers() {
+			return pojoEntityTuplizer.getEntityNameResolvers();
+		}
+
+		@Override
+		public String determineConcreteSubclassEntityName(
+				Object entityInstance, SessionFactoryImplementor factory) {
+			return pojoEntityTuplizer.determineConcreteSubclassEntityName( entityInstance, factory );
+		}
+
+		@Override
+		public Getter getIdentifierGetter() {
+			return pojoEntityTuplizer.getIdentifierGetter();
+		}
+
+		@Override
+		public Getter getVersionGetter() {
+			return pojoEntityTuplizer.getVersionGetter();
+		}
+
+		@Override
+		public ProxyFactory getProxyFactory() {
+			return null;
+		}
+
+		@Override
+		public Object[] getPropertyValues(Object entity) {
+			return pojoEntityTuplizer.getPropertyValues( entity );
+		}
+
+		@Override
+		public void setPropertyValues(Object entity, Object[] values) {
+			pojoEntityTuplizer.setPropertyValues( entity, values );
+		}
+
+		@Override
+		public Object getPropertyValue(Object entity, int i) {
+			return pojoEntityTuplizer.getPropertyValue( entity, i );
+		}
+
+		@Override
+		public Object instantiate() {
+			return pojoEntityTuplizer.instantiate();
+		}
+
+		@Override
+		public boolean isInstance(Object object) {
+			return pojoEntityTuplizer.isInstance( object );
+		}
+
+		@Override
+		public Class getMappedClass() {
+			return pojoEntityTuplizer.getMappedClass();
+		}
+
+		@Override
+		public Getter getGetter(int i) {
+			return pojoEntityTuplizer.getGetter( i );
+		}
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/LazyToOnesProxyMergeWithSubclassesTest.java

@@ -0,0 +1,865 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy.proxy;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+import org.hibernate.Hibernate;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.proxy.HibernateProxy;
+import org.hibernate.stat.Statistics;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.bytecode.enhancement.EnhancementOptions;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Gail Badner
+ */
+@TestForIssue( jiraKey = "HHH-13640" )
+@RunWith(BytecodeEnhancerRunner.class )
+@EnhancementOptions(lazyLoading = true)
+public class LazyToOnesProxyMergeWithSubclassesTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+		ssrb.applySetting( AvailableSettings.ALLOW_ENHANCEMENT_AS_PROXY, "true" );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( Animal.class );
+		sources.addAnnotatedClass( Primate.class );
+		sources.addAnnotatedClass( Human.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void mergeUpdatedHibernateProxy() {
+
+		checkAgeInNewSession( 1 );
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		final OtherEntity withInitializedHibernateProxy = doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().getSex();
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					return otherEntity;
+				}
+		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 1 );
+		stats.clear();
+
+		// merge updated HibernateProxy to updated HibernateProxy
+
+		withInitializedHibernateProxy.getHuman().setAge( 2 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().setAge( 3 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					final Human humanImpl = (Human) ( (HibernateProxy) otherEntity.getHuman() )
+							.getHibernateLazyInitializer()
+							.getImplementation();
+
+					session.merge( withInitializedHibernateProxy );
+					// TODO: Reference to associated HibernateProxy is changed
+					//       to the HibernateProxy's implementation.
+					assertSame( humanImpl, otherEntity.getHuman() );
+					assertEquals( 2, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 2 );
+		stats.clear();
+
+		// merge updated HibernateProxy to updated enhanced entity
+
+		withInitializedHibernateProxy.getHuman().setAge( 4 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertSame( human, otherEntity.getHuman() );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					human.setAge( 5 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					session.merge( withInitializedHibernateProxy );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertSame( human, otherEntity.getHuman() );
+					assertEquals( 4, human.getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 4 );
+		stats.clear();
+
+		// merge updated HibernateProxy to uninitialized HibernateProxy
+
+		withInitializedHibernateProxy.getHuman().setAge( 6 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					final Human humanHibernateProxy = otherEntity.getHuman();
+
+					session.merge( withInitializedHibernateProxy );
+
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					// TODO: Reference to associated HibernateProxy is changed
+					//       reference to the HibernateProxy's implementation.
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+					assertSame(
+							otherEntity.getHuman(),
+							( (HibernateProxy) humanHibernateProxy ).getHibernateLazyInitializer().getImplementation()
+					);
+
+					assertEquals( 6, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 6 );
+		stats.clear();
+
+		// merge updated HibernateProxy To uninitialized enhanced proxy
+
+		withInitializedHibernateProxy.getHuman().setAge( 7 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+
+					session.merge( withInitializedHibernateProxy );
+					assertSame( human, otherEntity.getHuman() );
+					assertTrue( Hibernate.isInitialized( human ) );
+
+					assertEquals( 7, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 7 );
+	}
+
+	@Test
+	public void mergeUpdatedEnhancedProxy() {
+
+		checkAgeInNewSession( 1 );
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		final OtherEntity withInitializedEnhancedProxy = doInHibernate(
+				this::sessionFactory,
+				session -> {
+
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().getSex();
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					return otherEntity;
+				}
+		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 1 );
+		stats.clear();
+
+		// merge updated enhanced proxy to updated HibernateProxy
+
+		withInitializedEnhancedProxy.getHuman().setAge( 2 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().setAge( 3 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					final Human humanImpl = (Human) ( (HibernateProxy) otherEntity.getHuman() )
+							.getHibernateLazyInitializer()
+							.getImplementation();
+
+					session.merge( withInitializedEnhancedProxy );
+					// TODO: Reference to HibernateProxy is changed
+					//       to the HibernateProxy's implementation.
+					assertSame( humanImpl, otherEntity.getHuman() );
+
+					assertEquals( 2, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 2 );
+		stats.clear();
+
+		// merge updated enhanced proxy to updated enhanced proxy
+
+		withInitializedEnhancedProxy.getHuman().setAge( 4 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertSame( human, otherEntity.getHuman() );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					human.setAge( 5 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					session.merge( withInitializedEnhancedProxy );
+					assertEquals( 4, human.getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 4 );
+		stats.clear();
+
+		// merge updated enhanced proxy to uninitialized HibernateProxy
+
+		withInitializedEnhancedProxy.getHuman().setAge( 6 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					session.merge( withInitializedEnhancedProxy );
+
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					// TODO: Reference in managed entity gets changed from a HibernateProxy
+					// to an initialized entity. This happens without enhancement as well.
+					//assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+					assertEquals( 6, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 6 );
+		stats.clear();
+
+		// merge updated enhanced proxy to uninitialized enhanced proxy
+
+		withInitializedEnhancedProxy.getHuman().setAge( 7 );
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+
+					session.merge( withInitializedEnhancedProxy );
+					assertSame( human, otherEntity.getHuman() );
+					assertTrue( Hibernate.isInitialized( human ) );
+
+					assertEquals( 7, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 7 );
+	}
+
+	@Test
+	public void mergeUninitializedHibernateProxy() {
+
+		checkAgeInNewSession( 1 );
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		final OtherEntity withUninitializedHibernateProxy = doInHibernate(
+				this::sessionFactory,
+				session -> {
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					return otherEntity;
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 1 );
+		stats.clear();
+
+		// merge uninitialized HibernateProxy to updated HibernateProxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().setAge( 3 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					final Human humanImpl = (Human) ( (HibernateProxy) otherEntity.getHuman() )
+							.getHibernateLazyInitializer()
+							.getImplementation();
+
+					session.merge( withUninitializedHibernateProxy );
+					//assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					// TODO: Reference to HibernateProxy is changed
+					//       to the HibernateProxy's implementation.
+					assertSame( humanImpl, otherEntity.getHuman() );
+
+					assertEquals( 3, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 3 );
+		stats.clear();
+
+		// merge uninitialized HibernateProxy to updated enhanced proxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertSame( human, otherEntity.getHuman() );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					human.setAge( 5 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					session.merge( withUninitializedHibernateProxy );
+					assertEquals( 5, human.getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+		stats.clear();
+
+		// merge uninitialized HibernateProxy to uninitialized HibernateProxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					session.merge( withUninitializedHibernateProxy );
+
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+		stats.clear();
+
+		// merge uninitialized HibernateProxy to uninitialized enhanced proxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+
+					session.merge( withUninitializedHibernateProxy );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+	}
+
+	@Test
+	public void testmergeUninitializedEnhancedProxy() {
+
+		checkAgeInNewSession( 1 );
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		final OtherEntity withUninitializedEnhancedProxy = doInHibernate(
+				this::sessionFactory,
+				session -> {
+
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+					return otherEntity;
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 1 );
+		stats.clear();
+
+		// merge uninitialized enhanced proxy to updated HibernateProxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					otherEntity.getHuman().setAge( 3 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					final Human humanImpl = (Human) ( (HibernateProxy) otherEntity.getHuman() )
+							.getHibernateLazyInitializer()
+							.getImplementation();
+
+					session.merge( withUninitializedEnhancedProxy );
+					// TODO: Reference to HibernateProxy is changed
+					//       to the HibernateProxy's implementation.
+					assertSame( humanImpl, otherEntity.getHuman() );
+
+					assertEquals( 3, otherEntity.getHuman().getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 3 );
+		stats.clear();
+
+		// merge uninitialized enhanced proxy to updated enhanced entity
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertSame( human, otherEntity.getHuman() );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					human.setAge( 5 );
+					assertTrue( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					session.merge( withUninitializedEnhancedProxy );
+					assertEquals( 5, human.getAge() );
+				}
+		);
+
+		assertEquals( 3, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+		stats.clear();
+
+		// merge uninitialized enhanced proxy to uninitialized HibernateProxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					session.merge( withUninitializedEnhancedProxy );
+
+					assertFalse( Hibernate.isInitialized( otherEntity.getHuman() ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+		stats.clear();
+
+		// merge uninitialized enhanced proxy to uninitialized enhanced proxy
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( human ) );
+					assertEquals( 0, stats.getPrepareStatementCount() );
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+
+					session.merge( withUninitializedEnhancedProxy );
+					assertSame( human, otherEntity.getHuman() );
+					assertFalse( Hibernate.isInitialized( human ) );
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		checkAgeInNewSession( 5 );
+	}
+
+	private void checkAgeInNewSession(int expectedAge) {
+
+		doInHibernate(
+				this::sessionFactory,
+				session -> {
+					final Human human = session.get( Human.class, "A Human" );
+					assertEquals( expectedAge, human.getAge() );
+				}
+		);
+
+	}
+
+	@Before
+	public void setupData() {
+		inTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					otherEntity.primate = human;
+					otherEntity.human = human;
+					otherEntity.human.setAge( 1 );
+
+					session.persist( human );
+					session.persist( otherEntity );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Human" ).executeUpdate();
+					session.createQuery( "delete from Primate" ).executeUpdate();
+					session.createQuery( "delete from Animal" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "Animal")
+	@Table(name = "Animal")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	public static abstract class Animal {
+
+		@Id
+		private String name;
+
+		private int age;
+
+		public String getName() {
+			return name;
+		}
+
+		protected void setName(String name) {
+			this.name = name;
+		}
+
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
+	}
+
+	@Entity(name = "Primate")
+	@Table(name = "Primate")
+	public static class Primate extends Animal {
+
+		public Primate(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Primate() {
+			// this form used by Hibernate
+		}
+	}
+
+	@Entity(name = "Human")
+	@Table(name = "Human")
+	public static class Human extends Primate {
+
+		private String sex;
+
+		public Human(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Human() {
+			// this form used by Hibernate
+		}
+
+		public String getSex() {
+			return sex;
+		}
+
+		public void setSex(String sex) {
+			this.sex = sex;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Animal animal = null;
+
+		@ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Primate primate = null;
+
+		@ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human human = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+
+		public Human getHuman() {
+			return human;
+		}
+
+		public void setHuman(Human human) {
+			this.human = human;
+		}
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/LazyToOnesProxyWithSubclassesStatelessTest.java

@@ -0,0 +1,332 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy.proxy;
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToOne;
+import javax.persistence.Table;
+
+import org.hibernate.Hibernate;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.proxy.HibernateProxy;
+import org.hibernate.stat.Statistics;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Gail Badner
+ */
+@TestForIssue( jiraKey = "HHH-13640" )
+@RunWith(BytecodeEnhancerRunner.class)
+public class LazyToOnesProxyWithSubclassesStatelessTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+		ssrb.applySetting( AvailableSettings.ALLOW_ENHANCEMENT_AS_PROXY, "true" );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( Animal.class );
+		sources.addAnnotatedClass( Primate.class );
+		sources.addAnnotatedClass( Human.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void testNewHibernateProxyAssociation() {
+		inStatelessTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.animal ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.animal ) );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@Test
+	public void testNewEnhancedProxyAssociation() {
+		inStatelessTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+
+	}
+
+	@Test
+	public void testExistingProxyAssociation() {
+		inStatelessTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					otherEntity.primate = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.animal ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "primate" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.primate ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.primate ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@Test
+	public void testExistingHibernateProxyAssociationLeafSubclass() {
+		inStatelessSession(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.animal = human;
+					otherEntity.primate = human;
+					otherEntity.human = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
+		inStatelessSession(
+				session -> {
+
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.animal ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "primate" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.primate ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.primate ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+
+		assertEquals( 1, stats.getPrepareStatementCount() );
+	}
+
+	@Test
+	public void testExistingEnhancedProxyAssociationLeafSubclassOnly() {
+		inStatelessSession(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+					session.insert( human );
+					session.insert( otherEntity );
+				}
+		);
+
+		inStatelessSession(
+				session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+
+					final OtherEntity otherEntity = (OtherEntity) session.get( OtherEntity.class, "test1" );
+					assertNull( otherEntity.animal );
+					assertNull( otherEntity.primate );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Human" ).executeUpdate();
+					session.createQuery( "delete from Primate" ).executeUpdate();
+					session.createQuery( "delete from Animal" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "Animal")
+	@Table(name = "Animal")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	public static abstract class Animal {
+
+		@Id
+		private String name;
+
+		private int age;
+
+		public String getName() {
+			return name;
+		}
+
+		protected void setName(String name) {
+			this.name = name;
+		}
+
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
+	}
+
+	@Entity(name = "Primate")
+	@Table(name = "Primate")
+	public static class Primate extends Animal {
+
+		public Primate(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Primate() {
+			// this form used by Hibernate
+		}
+	}
+
+	@Entity(name = "Human")
+	@Table(name = "Human")
+	public static class Human extends Primate {
+
+		private String sex;
+
+		public Human(String name) {
+			this();
+			setName( name );
+		}
+
+		protected Human() {
+			// this form used by Hibernate
+		}
+
+		public String getSex() {
+			return sex;
+		}
+
+		public void setSex(String sex) {
+			this.sex = sex;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Animal animal = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Primate primate = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		private Human human = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+
+		public Human getHuman() {
+			return human;
+		}
+
+		public void setHuman(Human human) {
+			this.human = human;
+		}
+	}
+}

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/LazyToOnesProxyWithSubclassesTest.java

@@ -31,8 +31,10 @@ import org.junit.After;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -154,7 +156,7 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 	}
 
 	@Test
-	public void testExistingProxyAssociationLeafSubclass() {
+	public void testExistingHibernateProxyAssociationLeafSubclass() {
 		inTransaction(
 				session -> {
 					Human human = new Human( "A Human" );
@@ -167,10 +169,11 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 				}
 		);
 
+		final Statistics stats = sessionFactory().getStatistics();
+		stats.clear();
+
 		inSession(
 				session -> {
-					final Statistics stats = sessionFactory().getStatistics();
-					stats.clear();
 
 					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
 					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
@@ -181,18 +184,101 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 					assertTrue( HibernateProxy.class.isInstance( otherEntity.primate ) );
 					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
 					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
-					// TODO: Should otherEntity.human be a narrowed HibernateProxy or
+
-					// an uninitialized non-HibernateProxy proxy?
 					assertEquals( 1, stats.getPrepareStatementCount() );
 
-					Human human = otherEntity.getHuman();
+					// Make sure human can still get loaded and not initialized.
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertFalse( Hibernate.isInitialized( human ) );
+
 					human.getName();
 					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.human ) );
 
 					human.getSex();
+
+					assertTrue( Hibernate.isInitialized( human ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.human ) );
 					assertEquals( 2, stats.getPrepareStatementCount() );
 				}
 		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+		stats.clear();
+
+		inSession(
+				session -> {
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "animal" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.animal ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.animal ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "primate" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.primate ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.primate ) );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					// Make sure human can still get loaded
+					final Human human = session.get( Human.class, "A Human" );
+					assertTrue( !HibernateProxy.class.isInstance( human ) );
+					assertTrue( Hibernate.isInitialized( human ) );
+					assertTrue( HibernateProxy.class.isInstance( otherEntity.getHuman() ) );
+
+					assertEquals( 2, stats.getPrepareStatementCount() );
+				}
+		);
+
+		assertEquals( 2, stats.getPrepareStatementCount() );
+
+	}
+
+	@Test
+	public void testExistingEnhancedProxyAssociationLeafSubclassOnly() {
+		inTransaction(
+				session -> {
+					Human human = new Human( "A Human" );
+					OtherEntity otherEntity = new OtherEntity( "test1" );
+					otherEntity.human = human;
+					session.persist( human );
+					session.persist( otherEntity );
+				}
+		);
+
+		doInHibernate(
+				this::sessionFactory, session -> {
+					final Statistics stats = sessionFactory().getStatistics();
+					stats.clear();
+
+					final OtherEntity otherEntity = session.get( OtherEntity.class, "test1" );
+					assertNull( otherEntity.animal );
+					assertNull( otherEntity.primate );
+					assertTrue( Hibernate.isPropertyInitialized( otherEntity, "human" ) );
+					assertFalse( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertEquals( 1, stats.getPrepareStatementCount() );
+
+					// Make sure human can still get loaded and not initialized.
+					final Human human = session.getReference( Human.class, "A Human" );
+					assertFalse( Hibernate.isInitialized( human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+
+					human.getName();
+					assertEquals( 1, stats.getPrepareStatementCount() );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+
+					human.getSex();
+					assertTrue( Hibernate.isInitialized( otherEntity.human ) );
+					assertFalse( HibernateProxy.class.isInstance( otherEntity.human ) );
+					assertEquals( 2, stats.getPrepareStatementCount() );
+
+					return otherEntity;
+				}
+		);
 	}
 
 	@After
@@ -215,6 +301,8 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 		@Id
 		private String name;
 
+		private int age;
+
 		public String getName() {
 			return name;
 		}
@@ -223,6 +311,13 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 			this.name = name;
 		}
 
+		public int getAge() {
+			return age;
+		}
+
+		public void setAge(int age) {
+			this.age = age;
+		}
 	}
 
 	@Entity(name = "Primate")
@@ -272,15 +367,15 @@ public class LazyToOnesProxyWithSubclassesTest extends BaseNonConfigCoreFunction
 
 		@ManyToOne(fetch = FetchType.LAZY)
 		@LazyToOne(LazyToOneOption.NO_PROXY)
-		protected Animal animal = null;
+		private Animal animal = null;
 
 		@ManyToOne(fetch = FetchType.LAZY)
 		@LazyToOne(LazyToOneOption.NO_PROXY)
-		protected Primate primate = null;
+		private Primate primate = null;
 
 		@ManyToOne(fetch = FetchType.LAZY)
 		@LazyToOne(LazyToOneOption.NO_PROXY)
-		protected Human human = null;
+		private Human human = null;
 
 		protected OtherEntity() {
 			// this form used by Hibernate

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/ProxyInitializeAndUpdateTest.java

@@ -27,6 +27,7 @@ import org.junit.runner.RunWith;
 import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -155,7 +156,8 @@ public class ProxyInitializeAndUpdateTest extends BaseNonConfigCoreFunctionalTes
 				session -> {
 					final Animal animal = session.load( Animal.class, "animal" );
 					assertFalse( Hibernate.isInitialized( animal ) );
-					session.merge( animalInitialized );
+					final Animal animalMerged = (Animal) session.merge( animalInitialized );
+					assertSame( animal, animalMerged );
 					assertTrue( Hibernate.isInitialized( animal ) );
 					assertEquals( 4, animal.getAge() );
 					assertEquals( "other", animal.getSex() );
@@ -204,7 +206,8 @@ public class ProxyInitializeAndUpdateTest extends BaseNonConfigCoreFunctionalTes
 					assertTrue( Hibernate.isInitialized( animal ) );
 					animal.setAge( 5 );
 					animal.setSex( "male" );
-					session.merge( animalInitialized );
+					final Animal animalMerged = (Animal) session.merge( animalInitialized );
+					assertSame( animal, animalMerged );
 					assertEquals( 4, animal.getAge() );
 					assertEquals( "other", animal.getSex() );
 				}
@@ -245,7 +248,8 @@ public class ProxyInitializeAndUpdateTest extends BaseNonConfigCoreFunctionalTes
 				session -> {
 					final Animal animal = session.load( Animal.class, "animal" );
 					assertFalse( Hibernate.isInitialized( animal ) );
-					session.merge( animalUninitialized );
+					final Animal animalMerged = (Animal) session.merge( animalUninitialized );
+					assertSame( animal, animalMerged );
 					assertFalse( Hibernate.isInitialized( animal ) );
 				}
 		);
@@ -283,11 +287,13 @@ public class ProxyInitializeAndUpdateTest extends BaseNonConfigCoreFunctionalTes
 
 		inTransaction(
 				session -> {
-					final Animal animal = session.get( Animal.class, "animal" );
+					final Animal animal = session.load( Animal.class, "animal" );
-					assertTrue( Hibernate.isInitialized( animal ) );
+					assertFalse( Hibernate.isInitialized( animal ) );
 					animal.setSex( "other" );
+					assertTrue( Hibernate.isInitialized( animal ) );
 					animal.setAge( 4 );
-					session.merge( animalUninitialized );
+					final Animal animalMerged = (Animal) session.merge( animalUninitialized );
+					assertSame( animal, animalMerged );
 					assertTrue( Hibernate.isInitialized( animal ) );
 					assertEquals( "other", animal.getSex() );
 					assertEquals( 4, animal.getAge() );

hibernate-core/src/test/java/org/hibernate/test/bytecode/enhancement/lazy/proxy/QueryScrollingWithInheritanceProxyTest.java

@@ -0,0 +1,327 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.bytecode.enhancement.lazy.proxy;
+
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+import org.hibernate.Hibernate;
+import org.hibernate.ScrollMode;
+import org.hibernate.ScrollableResults;
+import org.hibernate.Session;
+import org.hibernate.StatelessSession;
+import org.hibernate.annotations.LazyToOne;
+import org.hibernate.annotations.LazyToOneOption;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.dialect.DB2Dialect;
+import org.hibernate.query.Query;
+import org.hibernate.stat.spi.StatisticsImplementor;
+
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author Andrea Boriero
+ */
+@RunWith(BytecodeEnhancerRunner.class)
+public class QueryScrollingWithInheritanceProxyTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+		ssrb.applySetting( AvailableSettings.ALLOW_ENHANCEMENT_AS_PROXY, "true" );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( EmployeeParent.class );
+		sources.addAnnotatedClass( Employee.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void testScrollableWithStatelessSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final StatelessSession statelessSession = sessionFactory().openStatelessSession();
+
+		try {
+			statelessSession.beginTransaction();
+			Query<Employee> query = statelessSession.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						if ( "test1".equals( otherEntity.id ) ) {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( otherEntity.employeeParent, is( employee ) );
+						}
+						else {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( Hibernate.isInitialized( otherEntity.employeeParent ), is( false ) );
+						}
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			statelessSession.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( statelessSession.getTransaction().isActive() ) {
+				statelessSession.getTransaction().rollback();
+			}
+			statelessSession.close();
+		}
+	}
+
+	@Test
+	public void testScrollableWithSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final Session session = sessionFactory().openSession();
+
+		try {
+			session.beginTransaction();
+			Query<Employee> query = session.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						if ( "test1".equals( otherEntity.id ) ) {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( otherEntity.employeeParent, is( employee ) );
+						}
+						else {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( Hibernate.isInitialized( otherEntity.employeeParent ), is( false ) );
+						}
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			session.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( session.getTransaction().isActive() ) {
+				session.getTransaction().rollback();
+			}
+			session.close();
+		}
+	}
+
+	@Before
+	public void prepareTestData() {
+		inTransaction(
+				session -> {
+					Employee e1 = new Employee( "ENG1" );
+					Employee e2 = new Employee( "ENG2" );
+					OtherEntity other1 = new OtherEntity( "test1" );
+					OtherEntity other2 = new OtherEntity( "test2" );
+					e1.getOtherEntities().add( other1 );
+					e1.getOtherEntities().add( other2 );
+					e1.getParentOtherEntities().add( other1 );
+					e1.getParentOtherEntities().add( other2 );
+					other1.employee = e1;
+					other2.employee = e1;
+					other1.employeeParent = e1;
+					other2.employeeParent = e2;
+					session.persist( other1 );
+					session.persist( other2 );
+					session.persist( e1 );
+					session.persist( e2 );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Employee" ).executeUpdate();
+					session.createQuery( "delete from EmployeeParent" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "EmployeeParent")
+	@Table(name = "EmployeeParent")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	public static abstract class EmployeeParent {
+
+		@Id
+		private String dept;
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employeeParent", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> parentOtherEntities = new HashSet<>();
+
+		public Set<OtherEntity> getParentOtherEntities() {
+			if ( parentOtherEntities == null ) {
+				parentOtherEntities = new LinkedHashSet();
+			}
+			return parentOtherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pParentOtherEntites) {
+			parentOtherEntities = pParentOtherEntites;
+		}
+
+		public String getDept() {
+			return dept;
+		}
+
+		protected void setDept(String dept) {
+			this.dept = dept;
+		}
+
+	}
+
+	@Entity(name = "Employee")
+	@Table(name = "Employee")
+	public static class Employee extends EmployeeParent {
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employee", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> otherEntities = new HashSet<>();
+
+		public Employee(String dept) {
+			this();
+			setDept( dept );
+		}
+
+		protected Employee() {
+			// this form used by Hibernate
+		}
+
+		public Set<OtherEntity> getOtherEntities() {
+			if ( otherEntities == null ) {
+				otherEntities = new LinkedHashSet();
+			}
+			return otherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pOtherEntites) {
+			otherEntities = pOtherEntites;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		@JoinColumn(name = "Employee_Id")
+		protected Employee employee = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@LazyToOne(LazyToOneOption.NO_PROXY)
+		@JoinColumn(name = "EmployeeParent_Id")
+		protected EmployeeParent employeeParent = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/cfg/cache/DirectReferenceCacheEntriesTest.java

@@ -0,0 +1,72 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.cfg.cache;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+import org.hibernate.annotations.Immutable;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.cfg.Configuration;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+
+/**
+ * @author Andrea Boriero
+ */
+@TestForIssue(jiraKey = "HHH-13665")
+public class DirectReferenceCacheEntriesTest extends BaseCoreFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] { TheEntity.class };
+	}
+
+	@Override
+	protected void configure(Configuration configuration) {
+		configuration.setProperty( AvailableSettings.USE_DIRECT_REFERENCE_CACHE_ENTRIES, "true" );
+	}
+
+	@Before
+	public void setUp() {
+		doInHibernate( this::sessionFactory, session -> {
+			TheEntity theEntity = new TheEntity();
+			theEntity.setId( 1L );
+			session.persist( theEntity );
+		} );
+	}
+
+	@Test
+	public void testSelectANonCachablenEntity() {
+		doInHibernate( this::sessionFactory, session -> {
+			session.createQuery( "select t from TheEntity t", TheEntity.class ).getResultList();
+		} );
+	}
+
+	@Entity(name = "TheEntity")
+	@Table(name = "THE_ENTITY")
+	@Immutable
+	public static class TheEntity {
+		@Id
+		public Long id;
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/flush/TestHibernateFlushModeOnThreadLocalInactiveTransaction.java

@@ -0,0 +1,38 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.test.flush;
+
+import org.hibernate.FlushMode;
+import org.hibernate.Session;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.cfg.Configuration;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Test;
+
+/**
+ * Test for issue https://hibernate.atlassian.net/browse/HHH-13663
+ * 
+ * @author Luca Domenichini
+ */
+@TestForIssue(jiraKey = "HHH-13663")
+public class TestHibernateFlushModeOnThreadLocalInactiveTransaction extends BaseCoreFunctionalTestCase {
+
+	@Override
+	protected void configure(Configuration configuration) {
+		configuration.setProperty( AvailableSettings.CURRENT_SESSION_CONTEXT_CLASS, "thread" );
+	}
+
+	@Test
+	public void testHibernateFlushModeOnInactiveTransaction() {
+		try ( Session s = sessionFactory().getCurrentSession() ) {
+			//s.setFlushMode( FlushMode.AUTO ); // this does not throw (API is deprecated)
+			s.setHibernateFlushMode( FlushMode.AUTO ); // this should not throw even within an inactive transaction
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/hqlfetchscroll/QueryScrollingWithInheritanceTest.java

@@ -0,0 +1,318 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.hqlfetchscroll;
+
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+import org.hibernate.Hibernate;
+import org.hibernate.ScrollMode;
+import org.hibernate.ScrollableResults;
+import org.hibernate.Session;
+import org.hibernate.StatelessSession;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.SessionFactoryBuilder;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.dialect.DB2Dialect;
+import org.hibernate.query.Query;
+import org.hibernate.stat.spi.StatisticsImplementor;
+
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author Andrea Boriero
+ */
+public class QueryScrollingWithInheritanceTest extends BaseNonConfigCoreFunctionalTestCase {
+	@Override
+	protected void configureStandardServiceRegistryBuilder(StandardServiceRegistryBuilder ssrb) {
+		super.configureStandardServiceRegistryBuilder( ssrb );
+	}
+
+	@Override
+	protected void configureSessionFactoryBuilder(SessionFactoryBuilder sfb) {
+		super.configureSessionFactoryBuilder( sfb );
+		sfb.applyStatisticsSupport( true );
+		sfb.applySecondLevelCacheSupport( false );
+		sfb.applyQueryCacheSupport( false );
+	}
+
+	@Override
+	protected void applyMetadataSources(MetadataSources sources) {
+		super.applyMetadataSources( sources );
+		sources.addAnnotatedClass( EmployeeParent.class );
+		sources.addAnnotatedClass( Employee.class );
+		sources.addAnnotatedClass( OtherEntity.class );
+	}
+
+	@Test
+	public void testScrollableWithStatelessSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final StatelessSession statelessSession = sessionFactory().openStatelessSession();
+
+		try {
+			statelessSession.beginTransaction();
+			Query<Employee> query = statelessSession.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						if ( "test1".equals( otherEntity.id ) ) {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( otherEntity.employeeParent, is( employee ) );
+						}
+						else {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( Hibernate.isInitialized( otherEntity.employeeParent ), is( false ) );
+						}
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			statelessSession.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( statelessSession.getTransaction().isActive() ) {
+				statelessSession.getTransaction().rollback();
+			}
+			statelessSession.close();
+		}
+	}
+
+	@Test
+	public void testScrollableWithSession() {
+		final StatisticsImplementor stats = sessionFactory().getStatistics();
+		stats.clear();
+		ScrollableResults scrollableResults = null;
+		final Session session = sessionFactory().openSession();
+
+		try {
+			session.beginTransaction();
+			Query<Employee> query = session.createQuery(
+					"select distinct e from Employee e left join fetch e.otherEntities order by e.dept",
+					Employee.class
+			);
+			if ( getDialect() instanceof DB2Dialect ) {
+				/*
+					FetchingScrollableResultsImp#next() in order to check if the ResultSet is empty calls ResultSet#isBeforeFirst()
+					but the support for ResultSet#isBeforeFirst() is optional for ResultSets with a result
+					set type of TYPE_FORWARD_ONLY and db2 does not support it.
+			 	*/
+				scrollableResults = query.scroll( ScrollMode.SCROLL_INSENSITIVE );
+			}
+			else {
+				scrollableResults = query.scroll( ScrollMode.FORWARD_ONLY );
+			}
+
+			while ( scrollableResults.next() ) {
+				final Employee employee = (Employee) scrollableResults.get( 0 );
+				assertThat( Hibernate.isPropertyInitialized( employee, "otherEntities" ), is( true ) );
+				assertThat( Hibernate.isInitialized( employee.getOtherEntities() ), is( true ) );
+				if ( "ENG1".equals( employee.getDept() ) ) {
+					assertThat( employee.getOtherEntities().size(), is( 2 ) );
+					for ( OtherEntity otherEntity : employee.getOtherEntities() ) {
+						if ( "test1".equals( otherEntity.id ) ) {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( otherEntity.employeeParent, is( employee ) );
+						}
+						else {
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employee" ), is( true ) );
+							assertThat( otherEntity.employee, is( employee ) );
+							assertThat( Hibernate.isPropertyInitialized( otherEntity, "employeeParent" ), is( true ) );
+							assertThat( Hibernate.isInitialized( otherEntity.employeeParent ), is( false ) );
+						}
+					}
+				}
+				else {
+					assertThat( employee.getOtherEntities().size(), is( 0 ) );
+				}
+			}
+			session.getTransaction().commit();
+			assertThat( stats.getPrepareStatementCount(), is( 1L ) );
+		}
+		finally {
+			if ( scrollableResults != null ) {
+				scrollableResults.close();
+			}
+			if ( session.getTransaction().isActive() ) {
+				session.getTransaction().rollback();
+			}
+			session.close();
+		}
+	}
+
+	@Before
+	public void prepareTestData() {
+		inTransaction(
+				session -> {
+					Employee e1 = new Employee( "ENG1" );
+					Employee e2 = new Employee( "ENG2" );
+					OtherEntity other1 = new OtherEntity( "test1" );
+					OtherEntity other2 = new OtherEntity( "test2" );
+					e1.getOtherEntities().add( other1 );
+					e1.getOtherEntities().add( other2 );
+					e1.getParentOtherEntities().add( other1 );
+					e1.getParentOtherEntities().add( other2 );
+					other1.employee = e1;
+					other2.employee = e1;
+					other1.employeeParent = e1;
+					other2.employeeParent = e2;
+					session.persist( other1 );
+					session.persist( other2 );
+					session.persist( e1 );
+					session.persist( e2 );
+				}
+		);
+	}
+
+	@After
+	public void cleanUpTestData() {
+		inTransaction(
+				session -> {
+					session.createQuery( "delete from OtherEntity" ).executeUpdate();
+					session.createQuery( "delete from Employee" ).executeUpdate();
+					session.createQuery( "delete from EmployeeParent" ).executeUpdate();
+				}
+		);
+	}
+
+	@Entity(name = "EmployeeParent")
+	@Table(name = "EmployeeParent")
+	@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
+	public static abstract class EmployeeParent {
+
+		@Id
+		private String dept;
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employeeParent", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> parentOtherEntities = new HashSet<>();
+
+		public Set<OtherEntity> getParentOtherEntities() {
+			if ( parentOtherEntities == null ) {
+				parentOtherEntities = new LinkedHashSet();
+			}
+			return parentOtherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pParentOtherEntites) {
+			parentOtherEntities = pParentOtherEntites;
+		}
+
+		public String getDept() {
+			return dept;
+		}
+
+		protected void setDept(String dept) {
+			this.dept = dept;
+		}
+
+	}
+
+	@Entity(name = "Employee")
+	@Table(name = "Employee")
+	public static class Employee extends EmployeeParent {
+
+		@OneToMany(targetEntity = OtherEntity.class, mappedBy = "employee", fetch = FetchType.LAZY)
+		protected Set<OtherEntity> otherEntities = new HashSet<>();
+
+		public Employee(String dept) {
+			this();
+			setDept( dept );
+		}
+
+		protected Employee() {
+			// this form used by Hibernate
+		}
+
+		public Set<OtherEntity> getOtherEntities() {
+			if ( otherEntities == null ) {
+				otherEntities = new LinkedHashSet();
+			}
+			return otherEntities;
+		}
+
+		public void setOtherEntities(Set<OtherEntity> pOtherEntites) {
+			otherEntities = pOtherEntites;
+		}
+	}
+
+	@Entity(name = "OtherEntity")
+	@Table(name = "OtherEntity")
+	public static class OtherEntity {
+
+		@Id
+		private String id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@JoinColumn(name = "Employee_Id")
+		protected Employee employee = null;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@JoinColumn(name = "EmployeeParent_Id")
+		protected EmployeeParent employeeParent = null;
+
+		protected OtherEntity() {
+			// this form used by Hibernate
+		}
+
+		public OtherEntity(String id) {
+			this.id = id;
+		}
+
+		public String getId() {
+			return id;
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/manytomany/mapkey/ManyToManyWithMaykeyAndSchemaDefinitionTest.java

@@ -0,0 +1,135 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.test.manytomany.mapkey;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.JoinTable;
+import javax.persistence.ManyToMany;
+import javax.persistence.MapKey;
+import javax.persistence.Table;
+
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.cfg.Configuration;
+
+import org.hibernate.testing.DialectChecks;
+import org.hibernate.testing.RequiresDialectFeature;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author Andrea Boriero
+ */
+@TestForIssue(jiraKey = "HHH-4235")
+@RequiresDialectFeature(DialectChecks.SupportSchemaCreation.class)
+public class ManyToManyWithMaykeyAndSchemaDefinitionTest extends BaseCoreFunctionalTestCase {
+
+	@Override
+	protected void configure(Configuration configuration) {
+		configuration.setProperty( AvailableSettings.HBM2DDL_CREATE_SCHEMAS, "true" );
+	}
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] { EntityA.class, EntityB.class };
+	}
+
+	@Before
+	public void setUp() {
+		inTransaction(
+				session -> {
+					EntityA entityA = new EntityA();
+					entityA.setId( 1L );
+
+					EntityB entityB = new EntityB();
+					entityB.setId( 1L );
+					entityA.setEntityBs( "B", entityB );
+					session.persist( entityB );
+					session.persist( entityA );
+				}
+		);
+	}
+
+	@Test
+	public void testRetrievingTheMapGeneratesACorrectlyQuery() {
+
+		inTransaction(
+				session -> {
+					EntityA entityA = session.get( EntityA.class, 1L );
+					Collection<EntityB> values = entityA.getEntityBMap().values();
+					assertThat( values.size(), is( 1 ) );
+				}
+		);
+
+	}
+
+
+	@Entity(name = "EntityA")
+	@Table(name = "entitya", schema = "myschema")
+	public static class EntityA {
+
+		@Id
+		private Long id;
+
+		private String name;
+
+		@ManyToMany
+		@MapKey(name = "id")
+		@JoinTable(name = "entitya_entityb", schema = "myschema", joinColumns = @JoinColumn(name = "entitya_pk"), inverseJoinColumns = @JoinColumn(name = "entityb_pk"))
+		private Map<String, EntityB> entityBMap = new HashMap<>();
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+
+		public void setEntityBs(String key, EntityB entityB) {
+			this.entityBMap.put( key, entityB );
+		}
+
+		public Map<String, EntityB> getEntityBMap() {
+			return entityBMap;
+		}
+	}
+
+	@Entity(name = "EntityB")
+	@Table(name = "entityb", schema = "myschema")
+	public static class EntityB {
+		@Id
+		private Long id;
+
+		private String name;
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+
+	}
+}