HHH-19220 ClassCastException: class org.hibernate.bytecode.enhance.spi.LazyPropertyInitializer$1 cannot be cast to class java.lang.String

hibernate-envers/src/main/java/org/hibernate/envers/event/spi/EnversPostUpdateEventListenerImpl.java

@@ -4,6 +4,9 @@
  */
 package org.hibernate.envers.event.spi;
 
+import org.hibernate.bytecode.enhance.spi.LazyPropertyInitializer;
+import org.hibernate.bytecode.enhance.spi.interceptor.LazyAttributeLoadingInterceptor;
+import org.hibernate.bytecode.spi.BytecodeEnhancementMetadata;
 import org.hibernate.envers.boot.internal.EnversService;
 import org.hibernate.envers.internal.synchronization.AuditProcess;
 import org.hibernate.envers.internal.synchronization.work.AuditWorkUnit;
@@ -71,12 +74,30 @@ private Object[] postUpdateDBState(PostUpdateEvent event) {
 		final Object[] newDbState = event.getState().clone();
 		if ( event.getOldState() != null ) {
 			final EntityPersister entityPersister = event.getPersister();
+			final Object entity = event.getEntity();
+			final BytecodeEnhancementMetadata instrumentationMetadata = entityPersister.getInstrumentationMetadata();
+			final LazyAttributeLoadingInterceptor lazyAttributeLoadingInterceptor;
+			if ( instrumentationMetadata.isEnhancedForLazyLoading() ) {
+				lazyAttributeLoadingInterceptor = instrumentationMetadata.extractInterceptor( entity );
+			}
+			else {
+				lazyAttributeLoadingInterceptor = null;
+			}
 			for ( int i = 0; i < entityPersister.getPropertyNames().length; ++i ) {
 				if ( !entityPersister.getPropertyUpdateability()[i] ) {
 					// Assuming that PostUpdateEvent#getOldState() returns database state of the record before modification.
 					// Otherwise, we would have to execute SQL query to be sure of @Column(updatable = false) column value.
 					newDbState[i] = event.getOldState()[i];
 				}
+				// Properties that have not been initialized need to be fetched in order to bind their value in the
+				// AUDIT insert statement.
+				if ( newDbState[i] == LazyPropertyInitializer.UNFETCHED_PROPERTY ) {
+					assert lazyAttributeLoadingInterceptor != null : "Entity:`" + entityPersister.getEntityName() + "` with uninitialized property:` " + entityPersister.getPropertyNames()[i] + "` hasn't an associated LazyAttributeLoadingInterceptor";
+					event.getOldState()[i] = newDbState[i] = lazyAttributeLoadingInterceptor.fetchAttribute(
+							entity,
+							entityPersister.getPropertyNames()[i]
+					);
+				}
 			}
 		}
 		return newDbState;

hibernate-envers/src/test/java/org/hibernate/orm/test/envers/integration/lazy/LazyFieldsTest.java

@@ -0,0 +1,104 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.envers.integration.lazy;
+
+import org.hibernate.annotations.LazyGroup;
+import org.hibernate.envers.Audited;
+
+import org.hibernate.testing.bytecode.enhancement.extension.BytecodeEnhanced;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Basic;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+
+@JiraKey("")
+@BytecodeEnhanced
+@DomainModel(
+		annotatedClasses = {
+				LazyFieldsTest.TestEntity.class,
+		}
+)
+@SessionFactory
+public class LazyFieldsTest {
+
+	private static final Long ID = 1L;
+
+	@BeforeEach
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					TestEntity testEntity = new TestEntity( ID, "test data", "lazyString", "group A" );
+					session.persist( testEntity );
+				}
+		);
+	}
+
+	@Test
+	public void testUpdate(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					TestEntity testEntity = session.find( TestEntity.class, ID );
+					testEntity.setData( "modified test data" );
+				}
+		);
+	}
+
+	@Entity(name = "TestEntity")
+	public static class TestEntity {
+		@Id
+		private Long id;
+
+		@Audited
+		@Basic(optional = false)
+		private String data;
+
+		@Audited
+		@Basic(fetch = FetchType.LAZY)
+		private String lazyString;
+
+		@Audited
+		@Basic(fetch = FetchType.LAZY)
+		@LazyGroup("a")
+		private String lazyStringGroupA;
+
+		public TestEntity() {
+		}
+
+		public TestEntity(Long id, String data, String lazyString, String anotherLazyString) {
+			this.id = id;
+			this.data = data;
+			this.lazyString = lazyString;
+			this.lazyStringGroupA = anotherLazyString;
+		}
+
+		public Long getId() {
+			return id;
+		}
+
+		public String getData() {
+			return data;
+		}
+
+		public void setData(String data) {
+			this.data = data;
+		}
+
+		public String getLazyString() {
+			return lazyString;
+		}
+
+		public String getLazyStringGroupA() {
+			return lazyStringGroupA;
+		}
+	}
+
+}