From 2171d3b24add79ef60b38bc0a678824b2cc8870c Mon Sep 17 00:00:00 2001
From: Andrea Boriero <andrea@hibernate.org>
Date: Fri, 18 Nov 2022 12:45:16 +0100
Subject: [PATCH] HHH-15606 @OneToOne(mappedBy = ..., fetch = LAZY) in embedded
 leads to IllegalArgumentException: Can not set [...] to
 LazyPropertyInitializer

---
 .../EntityDelayedFetchInitializer.java        | 21 ++++++++++++-------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/hibernate-core/src/main/java/org/hibernate/sql/results/graph/entity/internal/EntityDelayedFetchInitializer.java b/hibernate-core/src/main/java/org/hibernate/sql/results/graph/entity/internal/EntityDelayedFetchInitializer.java
index a05ec80a9f..de725ea871 100644
--- a/hibernate-core/src/main/java/org/hibernate/sql/results/graph/entity/internal/EntityDelayedFetchInitializer.java
+++ b/hibernate-core/src/main/java/org/hibernate/sql/results/graph/entity/internal/EntityDelayedFetchInitializer.java
@@ -23,6 +23,7 @@
 import org.hibernate.sql.results.graph.AbstractFetchParentAccess;
 import org.hibernate.sql.results.graph.DomainResultAssembler;
 import org.hibernate.sql.results.graph.FetchParentAccess;
+import org.hibernate.sql.results.graph.embeddable.EmbeddableInitializer;
 import org.hibernate.sql.results.graph.entity.AbstractEntityInitializer;
 import org.hibernate.sql.results.graph.entity.EntityInitializer;
 import org.hibernate.sql.results.graph.entity.LoadingEntityEntry;
@@ -110,11 +111,10 @@ public void resolveInstance(RowProcessingState rowProcessingState) {
 				}
 			}
 			if ( entityInstance == null ) {
-				if ( referencedModelPart.isOptional() && parentAccess != null && parentAccess.getInitializedPart()
-						.findContainingEntityMapping()
-						.getEntityPersister()
-						.getBytecodeEnhancementMetadata()
-						.isEnhancedForLazyLoading() ) {
+				if ( referencedModelPart.isOptional()
+						&& parentAccess != null
+						&& !parentAccess.isEmbeddableInitializer()
+						&& isEnhancedForLazyLoading( parentAccess ) ) {
 					entityInstance = LazyPropertyInitializer.UNFETCHED_PROPERTY;
 				}
 				else {
@@ -138,9 +138,9 @@ public void resolveInstance(RowProcessingState rowProcessingState) {
 						final PersistenceContext persistenceContext = session.getPersistenceContextInternal();
 						entityInstance = persistenceContext.getEntity( euk );
 						if ( entityInstance == null ) {
-							if ( ( (AbstractEntityInitializer) this.parentAccess.findFirstEntityDescriptorAccess() ).getEntityDescriptor()
-									.getBytecodeEnhancementMetadata()
-									.isEnhancedForLazyLoading() ) {
+							if ( parentAccess != null
+									&& !parentAccess.isEmbeddableInitializer()
+									&& isEnhancedForLazyLoading( parentAccess ) ) {
 								return;
 							}
 							entityInstance = ( (UniqueKeyLoadable) concreteDescriptor ).loadByUniqueKey(
@@ -179,6 +179,11 @@ public void resolveInstance(RowProcessingState rowProcessingState) {
 		}
 	}
 
+	private static boolean isEnhancedForLazyLoading(FetchParentAccess parentAccess) {
+		return parentAccess.findFirstEntityInitializer().getEntityDescriptor().getBytecodeEnhancementMetadata()
+				.isEnhancedForLazyLoading();
+	}
+
 	@Override
 	public void initializeInstance(RowProcessingState rowProcessingState) {
 		// nothing to do