Infer hints for Hibernate generators

This commit updates
PersistenceManagedTypesBeanRegistrationAotProcessor
in order to infer hints for Hibernate annotations meta
annotated with `@ValueGenerationType` (like `@CreationTimestamp`)
and `@IdGeneratorType`.

`@GenericGenerator` is not supported as it is deprecated as of
Hibernate 6.5.

Closes gh-32842

spring-orm/src/main/java/org/springframework/orm/jpa/persistenceunit/PersistenceManagedTypesBeanRegistrationAotProcessor.java

@@ -188,38 +188,53 @@ class PersistenceManagedTypesBeanRegistrationAotProcessor implements BeanRegistr
 
 		@SuppressWarnings("unchecked")
 		private void contributeHibernateHints(RuntimeHints hints, @Nullable ClassLoader classLoader, Class<?> managedClass) {
-			Class<? extends Annotation> embeddableInstantiatorClass = loadEmbeddableInstantiatorClass(classLoader);
-			if (embeddableInstantiatorClass == null) {
-				return;
-			}
 			ReflectionHints reflection = hints.reflection();
-			registerInstantiatorForReflection(reflection,
-					AnnotationUtils.findAnnotation(managedClass, embeddableInstantiatorClass));
-			ReflectionUtils.doWithFields(managedClass, field -> {
-				registerInstantiatorForReflection(reflection,
-						AnnotationUtils.findAnnotation(field, embeddableInstantiatorClass));
-				registerInstantiatorForReflection(reflection,
-						AnnotationUtils.findAnnotation(field.getType(), embeddableInstantiatorClass));
-			});
-		}
 
-		private void registerInstantiatorForReflection(ReflectionHints reflection, @Nullable Annotation annotation) {
+			Class<? extends Annotation> embeddableInstantiatorClass = loadClass("org.hibernate.annotations.EmbeddableInstantiator", classLoader);
-			if (annotation == null) {
+			if (embeddableInstantiatorClass != null) {
-				return;
+				registerForReflection(reflection,
+						AnnotationUtils.findAnnotation(managedClass, embeddableInstantiatorClass), "value");
+				ReflectionUtils.doWithFields(managedClass, field -> {
+					registerForReflection(reflection,
+							AnnotationUtils.findAnnotation(field, embeddableInstantiatorClass), "value");
+					registerForReflection(reflection,
+							AnnotationUtils.findAnnotation(field.getType(), embeddableInstantiatorClass), "value");
+				});
+			}
+
+			Class<? extends Annotation> valueGenerationTypeClass = loadClass("org.hibernate.annotations.ValueGenerationType", classLoader);
+			if (valueGenerationTypeClass != null) {
+				ReflectionUtils.doWithFields(managedClass, field -> registerForReflection(reflection,
+						AnnotationUtils.findAnnotation(field, valueGenerationTypeClass), "generatedBy"));
+				ReflectionUtils.doWithMethods(managedClass, method -> registerForReflection(reflection,
+						AnnotationUtils.findAnnotation(method, valueGenerationTypeClass), "generatedBy"));
+			}
+
+			Class<? extends Annotation> idGeneratorTypeClass = loadClass("org.hibernate.annotations.IdGeneratorType", classLoader);
+			if (idGeneratorTypeClass != null) {
+				ReflectionUtils.doWithFields(managedClass, field -> registerForReflection(reflection,
+						AnnotationUtils.findAnnotation(field, idGeneratorTypeClass), "value"));
+				ReflectionUtils.doWithMethods(managedClass, method -> registerForReflection(reflection,
+						AnnotationUtils.findAnnotation(method, idGeneratorTypeClass), "value"));
 			}
-			Class<?> embeddableInstantiatorClass = (Class<?>) AnnotationUtils.getAnnotationAttributes(annotation).get("value");
-			reflection.registerType(embeddableInstantiatorClass, MemberCategory.INVOKE_DECLARED_CONSTRUCTORS);
 		}
 
 		@Nullable
-		private static Class<? extends Annotation> loadEmbeddableInstantiatorClass(@Nullable ClassLoader classLoader) {
+		private static Class<? extends Annotation> loadClass(String className, @Nullable ClassLoader classLoader) {
 			try {
-				return (Class<? extends Annotation>) ClassUtils.forName(
+				return (Class<? extends Annotation>) ClassUtils.forName(className, classLoader);
-						"org.hibernate.annotations.EmbeddableInstantiator", classLoader);
 			}
 			catch (ClassNotFoundException ex) {
 				return null;
 			}
 		}
+
+		private void registerForReflection(ReflectionHints reflection, @Nullable Annotation annotation, String attribute) {
+			if (annotation == null) {
+				return;
+			}
+			Class<?> embeddableInstantiatorClass = (Class<?>) AnnotationUtils.getAnnotationAttributes(annotation).get(attribute);
+			reflection.registerType(embeddableInstantiatorClass, MemberCategory.INVOKE_DECLARED_CONSTRUCTORS);
+		}
 	}
 }

spring-orm/src/test/java/org/springframework/orm/jpa/hibernate/domain/Book.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2002-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.orm.jpa.hibernate.domain;
+
+import java.time.Instant;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import org.hibernate.annotations.CreationTimestamp;
+
+@Entity
+public class Book {
+
+	@Id
+	private Long id;
+
+	private String title;
+
+	@CreationTimestamp
+	private Instant createdOn;
+
+	public Book() {
+	}
+
+	public Long getId() {
+		return id;
+	}
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public String getTitle() {
+		return title;
+	}
+
+	public void setTitle(String title) {
+		this.title = title;
+	}
+
+	public Instant getCreatedOn() {
+		return createdOn;
+	}
+
+	public void setCreatedOn(Instant createdOn) {
+		this.createdOn = createdOn;
+	}
+}

spring-orm/src/test/java/org/springframework/orm/jpa/persistenceunit/PersistenceManagedTypesBeanRegistrationAotProcessorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,6 +21,7 @@ import java.util.function.Consumer;
 
 import javax.sql.DataSource;
 
+import org.hibernate.tuple.CreationTimestampGeneration;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.aot.hint.MemberCategory;
@@ -30,7 +31,6 @@ import org.springframework.aot.test.generate.TestGenerationContext;
 import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.context.aot.ApplicationContextAotGenerator;
 import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.core.io.ResourceLoader;
@@ -64,7 +64,7 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 	@Test
 	void processEntityManagerWithPackagesToScan() {
 		GenericApplicationContext context = new AnnotationConfigApplicationContext();
-		context.registerBean(EntityManagerWithPackagesToScanConfiguration.class);
+		context.registerBean(JpaDomainConfiguration.class);
 		compile(context, (initializer, compiled) -> {
 			GenericApplicationContext freshApplicationContext = toFreshApplicationContext(
 					initializer);
@@ -75,14 +75,14 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 					EmployeeLocationConverter.class.getName());
 			assertThat(persistenceManagedTypes.getManagedPackages()).isEmpty();
 			assertThat(freshApplicationContext.getBean(
-					EntityManagerWithPackagesToScanConfiguration.class).scanningInvoked).isFalse();
+					JpaDomainConfiguration.class).scanningInvoked).isFalse();
 		});
 	}
 
 	@Test
-	void contributeHints() {
+	void contributeJpaHints() {
 		GenericApplicationContext context = new AnnotationConfigApplicationContext();
-		context.registerBean(EntityManagerWithPackagesToScanConfiguration.class);
+		context.registerBean(JpaDomainConfiguration.class);
 		contributeHints(context, hints -> {
 			assertThat(RuntimeHintsPredicates.reflection().onType(DriversLicense.class)
 					.withMemberCategories(MemberCategory.DECLARED_FIELDS)).accepts(hints);
@@ -108,6 +108,15 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 		});
 	}
 
+	@Test
+	void contributeHibernateHints() {
+		GenericApplicationContext context = new AnnotationConfigApplicationContext();
+		context.registerBean(HibernateDomainConfiguration.class);
+		contributeHints(context, hints ->
+				assertThat(RuntimeHintsPredicates.reflection().onType(CreationTimestampGeneration.class)
+				.withMemberCategories(MemberCategory.INVOKE_DECLARED_CONSTRUCTORS)).accepts(hints));
+	}
+
 
 	@SuppressWarnings("unchecked")
 	private void compile(GenericApplicationContext applicationContext,
@@ -135,10 +144,25 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 		result.accept(generationContext.getRuntimeHints());
 	}
 
-	@Configuration(proxyBeanMethods = false)
+	public static class JpaDomainConfiguration extends AbstractEntityManagerWithPackagesToScanConfiguration {
-	public static class EntityManagerWithPackagesToScanConfiguration {
 
-		private boolean scanningInvoked;
+		@Override
+		protected String packageToScan() {
+			return "org.springframework.orm.jpa.domain";
+		}
+	}
+
+	public static class HibernateDomainConfiguration extends AbstractEntityManagerWithPackagesToScanConfiguration {
+
+		@Override
+		protected String packageToScan() {
+			return "org.springframework.orm.jpa.hibernate.domain";
+		}
+	}
+
+	public abstract static class AbstractEntityManagerWithPackagesToScanConfiguration {
+
+		protected boolean scanningInvoked;
 
 		@Bean
 		public DataSource mockDataSource() {
@@ -156,7 +180,7 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 		public PersistenceManagedTypes persistenceManagedTypes(ResourceLoader resourceLoader) {
 			this.scanningInvoked = true;
 			return new PersistenceManagedTypesScanner(resourceLoader)
-					.scan("org.springframework.orm.jpa.domain");
+					.scan(packageToScan());
 		}
 
 		@Bean
@@ -169,6 +193,8 @@ class PersistenceManagedTypesBeanRegistrationAotProcessorTests {
 			return entityManagerFactoryBean;
 		}
 
+		protected abstract String packageToScan();
+
 	}
 
 }