HHH-12273 - Load Proxy by its identifier should consider the Session UUID

hibernate-core/src/main/java/org/hibernate/proxy/AbstractLazyInitializer.java

@@ -43,8 +43,6 @@ public abstract class AbstractLazyInitializer implements LazyInitializer {
 	private String sessionFactoryUuid;
 	private boolean allowLoadOutsideTransaction;
 
-	private boolean initializeProxyWhenAccessingIdentifier;
-
 	/**
 	 * For serialization from the non-pojo initializers (HHH-3309)
 	 */
@@ -67,8 +65,6 @@ public abstract class AbstractLazyInitializer implements LazyInitializer {
 		}
 		else {
 			setSession( session );
-			initializeProxyWhenAccessingIdentifier = session.getFactory().getSessionFactoryOptions()
-					.getJpaCompliance().isJpaProxyComplianceEnabled();
 		}
 	}
 
@@ -79,12 +75,18 @@ public abstract class AbstractLazyInitializer implements LazyInitializer {
 
 	@Override
 	public final Serializable getIdentifier() {
-		if ( isUninitialized() && initializeProxyWhenAccessingIdentifier ) {
+		if ( isUninitialized() && isInitializeProxyWhenAccessingIdentifier() ) {
 			initialize();
 		}
 		return id;
 	}
 
+	private boolean isInitializeProxyWhenAccessingIdentifier() {
+		return session != null && session.getFactory()
+				.getSessionFactoryOptions()
+				.getJpaCompliance().isJpaProxyComplianceEnabled();
+	}
+
 	@Override
 	public final void setIdentifier(Serializable id) {
 		this.id = id;

hibernate-core/src/test/java/org/hibernate/jpa/test/ops/GetLoadJpaComplianceDifferentSessionsTest.java

@@ -0,0 +1,82 @@
+/*
+ * 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.jpa.test.ops;
+
+import java.util.Map;
+import javax.persistence.EntityManagerFactory;
+
+import org.hibernate.Session;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.jpa.boot.spi.Bootstrap;
+import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
+
+import org.hibernate.testing.TestForIssue;
+import org.junit.Test;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * @author Vlad Mihalcea
+ */
+@TestForIssue( jiraKey = "HHH-12273" )
+public class GetLoadJpaComplianceDifferentSessionsTest extends BaseEntityManagerFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] {
+			Workload.class,
+		};
+	}
+
+	@Override
+	@SuppressWarnings( "unchecked" )
+	protected void addConfigOptions(Map options) {
+		options.put( AvailableSettings.JPA_PROXY_COMPLIANCE, Boolean.FALSE.toString() );
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9856" )
+	public void testReattachEntityToSessionWithJpaComplianceProxy() {
+		final Integer _workloadId = doInJPA( this::entityManagerFactory, entityManager -> {
+			Workload workload = new Workload();
+			workload.load = 123;
+			workload.name = "Package";
+			entityManager.persist( workload );
+
+			return workload.getId();
+		} );
+
+		Workload _workload = doInJPA( this::entityManagerFactory, entityManager -> {
+			return entityManager.getReference( Workload.class, _workloadId );
+		} );
+
+		Map settings = buildSettings();
+		settings.put( AvailableSettings.JPA_PROXY_COMPLIANCE, Boolean.TRUE.toString() );
+		settings.put( AvailableSettings.HBM2DDL_AUTO, "none" );
+
+		EntityManagerFactory newEntityManagerFactory =  Bootstrap
+			.getEntityManagerFactoryBuilder(
+					new TestingPersistenceUnitDescriptorImpl( getClass().getSimpleName() ),
+					settings )
+			.build();
+
+		try {
+			doInJPA( () -> newEntityManagerFactory, entityManager -> {
+				entityManager.unwrap( Session.class ).update( _workload );
+
+				_workload.getId();
+			});
+		}
+		finally {
+			newEntityManagerFactory.close();
+		}
+
+		assertEquals( "Package", _workload.getName() );
+	}
+}
+