HHH-16911 Integration test for SessionFactory using callbacks to not leak ClassLoader

hibernate-core/src/test/java/org/hibernate/orm/test/bootstrap/registry/classloading/HibernateCallbacksTestAction.java

@@ -0,0 +1,53 @@
+/*
+ * 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.orm.test.bootstrap.registry.classloading;
+
+import java.util.Collections;
+import java.util.List;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.EntityManagerFactory;
+import jakarta.persistence.Id;
+import jakarta.persistence.PrePersist;
+import jakarta.persistence.Transient;
+
+/**
+ * A test scenario to be used with {@link HibernateClassLoaderLeaksTest};
+ * the crucial aspect is that we're triggering a lookup of a JPA callback
+ * method.
+ */
+public class HibernateCallbacksTestAction extends HibernateLoadingTestAction {
+
+	protected void actionOnHibernate(EntityManagerFactory emf) {
+		try (final EntityManager entityManager = emf.createEntityManager() ) {
+			Booking b = new Booking();
+			b.id = Long.valueOf( 1l );
+			entityManager.persist( b ); //to trigger the @PrePersist invocation
+		}
+	}
+
+	protected List<String> getManagedClassNames() {
+		return Collections.singletonList( Booking.class.getName() );
+	}
+
+	@Entity(name = "booking")
+	private static class Booking {
+		@Id Long id;
+		@Transient String legacyIdentifier;
+
+		@PrePersist
+		public void computeLegacyIdentifier() {
+			//Details are not important, just making something up.
+			if ( legacyIdentifier == null && id != null ) {
+				this.legacyIdentifier = id.toString();
+			}
+		}
+
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/orm/test/bootstrap/registry/classloading/HibernateClassLoaderLeaksTest.java

@@ -58,6 +58,11 @@ public class HibernateClassLoaderLeaksTest {
 		ClassLoaderLeakDetector.assertNotLeakingAction( HibernateLoadingTestAction.class.getName() );
 	}
 
+	@Test
+	public void hibernateDoesNotLeakClassloaderWithCallbacks() {
+		ClassLoaderLeakDetector.assertNotLeakingAction( HibernateCallbacksTestAction.class.getName() );
+	}
+
 	private static void cleanup(Driver driver) {
 		System.out.println( "Attempting de-registration of driver: " + driver );
 		try {

hibernate-core/src/test/java/org/hibernate/orm/test/bootstrap/registry/classloading/HibernateLoadingTestAction.java

@@ -9,9 +9,12 @@ package org.hibernate.orm.test.bootstrap.registry.classloading;
 import java.sql.Driver;
 import java.sql.DriverManager;
 import java.sql.SQLException;
+import java.util.Collections;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
+import org.hibernate.SessionFactory;
 import org.hibernate.jpa.boot.spi.Bootstrap;
 import org.hibernate.orm.test.jpa.BaseEntityManagerFunctionalTestCase;
 
@@ -22,25 +25,50 @@ import jakarta.persistence.EntityManagerFactory;
  * this is meant to test against classloader leaks, so needs
  * to be packaged as a Runnable rather than using our usual
  * testing facilities.
+ * @see HibernateClassLoaderLeaksTest
  */
 public class HibernateLoadingTestAction extends NotLeakingTestAction implements Runnable {
 
 	@Override
-	public void run() {
+	public final void run() {
 		super.run(); //for basic sanity self-check
 		final Map config = new HashMap();
 		EntityManagerFactory emf = Bootstrap.getEntityManagerFactoryBuilder(
-				new BaseEntityManagerFunctionalTestCase.TestingPersistenceUnitDescriptorImpl( getClass().getSimpleName() ),
+				new BaseEntityManagerFunctionalTestCase.TestingPersistenceUnitDescriptorImpl( getClass().getSimpleName() ) {
+					@Override
+					public boolean isExcludeUnlistedClasses() {
+						return true;
+					}
+
+					@Override
+					public List<String> getManagedClassNames() {
+						return HibernateLoadingTestAction.this.getManagedClassNames();
+					}
+				},
 				config
 		).build();
 		try {
-			emf.close();
+			checkExpectedClassLoader( emf.unwrap( SessionFactory.class ).getClass() );
+			actionOnHibernate( emf );
 		}
 		finally {
-			cleanupJDBCDrivers();
+			try {
+				emf.close();
+			}
+			finally {
+				cleanupJDBCDrivers();
+			}
 		}
 	}
 
+	protected void actionOnHibernate(EntityManagerFactory emf) {
+		//no-op
+	}
+
+	protected List<String> getManagedClassNames() {
+		return Collections.emptyList();
+	}
+
 	private void cleanupJDBCDrivers() {
 		DriverManager.drivers().forEach( this::deregister );
 	}

hibernate-core/src/test/java/org/hibernate/orm/test/bootstrap/registry/classloading/NotLeakingTestAction.java

@@ -14,7 +14,11 @@ public class NotLeakingTestAction implements Runnable {
 
 	@Override
 	public void run() {
-		final ClassLoader owningClassloader = getClass().getClassLoader();
+		checkExpectedClassLoader( getClass() );
+	}
+
+	protected void checkExpectedClassLoader(Class aClass) {
+		final ClassLoader owningClassloader = aClass.getClassLoader();
 		if ( !owningClassloader.getName().equals( "TestIsolatedIsolatedClassLoader" ) ) {
 			throw new IllegalStateException( "Not being loaded by the expected classloader" );
 		}