Add support of declarative use of reflection

This commit adds a `@Reflective` annotation that can be used to declare
that the annotated element requires reflection at runtime. By default,
the annotated element is exposed but this can be customized by
specifying a dedicated `ReflectiveProcessor`.

Closes gh-28469

spring-context/src/main/java/org/springframework/context/aot/ReflectiveProcessorBeanRegistrationAotProcessor.java

@@ -0,0 +1,149 @@
+/*
+ * Copyright 2002-2022 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.context.aot;
+
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Constructor;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Consumer;
+
+import org.springframework.aot.generate.GenerationContext;
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.ReflectionHints;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.TypeHint.Builder;
+import org.springframework.aot.hint.annotation.Reflective;
+import org.springframework.aot.hint.annotation.ReflectiveProcessor;
+import org.springframework.aot.hint.support.RuntimeHintsUtils;
+import org.springframework.beans.BeanUtils;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationAotProcessor;
+import org.springframework.beans.factory.aot.BeanRegistrationCode;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.core.annotation.MergedAnnotation;
+import org.springframework.core.annotation.MergedAnnotations;
+import org.springframework.lang.Nullable;
+import org.springframework.util.ReflectionUtils;
+
+/**
+ * AOT {@code BeanRegistrationAotProcessor} that detects the presence of
+ * {@link Reflective @Reflective} on annotated elements and invoke the
+ * underlying {@link ReflectiveProcessor} implementations.
+ *
+ * @author Stephane Nicoll
+ */
+class ReflectiveProcessorBeanRegistrationAotProcessor implements BeanRegistrationAotProcessor {
+
+	private final Map<Class<? extends ReflectiveProcessor>, ReflectiveProcessor> processors = new HashMap<>();
+
+	@Nullable
+	@Override
+	public BeanRegistrationAotContribution processAheadOfTime(RegisteredBean registeredBean) {
+		Class<?> beanClass = registeredBean.getBeanClass();
+		Set<Entry> entries = new LinkedHashSet<>();
+		if (isReflective(beanClass)) {
+			entries.add(createEntry(beanClass));
+		}
+		doWithReflectiveConstructors(beanClass, constructor ->
+				entries.add(createEntry(constructor)));
+		ReflectionUtils.doWithFields(beanClass, field ->
+				entries.add(createEntry(field)), this::isReflective);
+		ReflectionUtils.doWithMethods(beanClass, method ->
+				entries.add(createEntry(method)), this::isReflective);
+		if (!entries.isEmpty()) {
+			return new ReflectiveProcessorBeanRegistrationAotContribution(entries);
+		}
+		return null;
+	}
+
+	private void doWithReflectiveConstructors(Class<?> beanClass, Consumer<Constructor<?>> consumer) {
+		for (Constructor<?> constructor : beanClass.getDeclaredConstructors()) {
+			if (isReflective(constructor)) {
+				consumer.accept(constructor);
+			}
+		}
+	}
+
+	private boolean isReflective(AnnotatedElement element) {
+		return MergedAnnotations.from(element).isPresent(Reflective.class);
+	}
+
+	@SuppressWarnings("unchecked")
+	private Entry createEntry(AnnotatedElement element) {
+		Class<? extends ReflectiveProcessor>[] processorClasses = (Class<? extends ReflectiveProcessor>[])
+				MergedAnnotations.from(element).get(Reflective.class).getClassArray("value");
+		List<ReflectiveProcessor> processors = Arrays.stream(processorClasses).distinct()
+				.map(processorClass -> this.processors.computeIfAbsent(processorClass, BeanUtils::instantiateClass))
+				.toList();
+		ReflectiveProcessor processorToUse = (processors.size() == 1 ? processors.get(0)
+				: new DelegateReflectiveProcessor(processors));
+		return new Entry(element, processorToUse);
+	}
+
+	static class DelegateReflectiveProcessor implements ReflectiveProcessor {
+
+		private final Iterable<ReflectiveProcessor> processors;
+
+		public DelegateReflectiveProcessor(Iterable<ReflectiveProcessor> processors) {
+			this.processors = processors;
+		}
+
+		@Override
+		public void registerReflectionHints(ReflectionHints hints, AnnotatedElement element) {
+			this.processors.forEach(processor -> processor.registerReflectionHints(hints, element));
+		}
+
+	}
+
+	private record Entry(AnnotatedElement element, ReflectiveProcessor processor) {}
+
+	private static class ReflectiveProcessorBeanRegistrationAotContribution implements BeanRegistrationAotContribution {
+
+		private static final Consumer<Builder> ANNOTATION_CUSTOMIZATIONS = hint -> hint.withMembers(MemberCategory.INVOKE_PUBLIC_METHODS);
+
+		private final Iterable<Entry> entries;
+
+		public ReflectiveProcessorBeanRegistrationAotContribution(Iterable<Entry> entries) {
+			this.entries = entries;
+		}
+
+		@Override
+		public void applyTo(GenerationContext generationContext, BeanRegistrationCode beanRegistrationCode) {
+			RuntimeHints runtimeHints = generationContext.getRuntimeHints();
+			runtimeHints.reflection().registerType(Reflective.class, ANNOTATION_CUSTOMIZATIONS);
+			this.entries.forEach(entry -> {
+				AnnotatedElement element = entry.element();
+				entry.processor().registerReflectionHints(runtimeHints.reflection(), element);
+				registerAnnotationIfNecessary(runtimeHints, element);
+			});
+		}
+
+		private void registerAnnotationIfNecessary(RuntimeHints hints, AnnotatedElement element) {
+			MergedAnnotation<Reflective> reflectiveAnnotation = MergedAnnotations.from(element).get(Reflective.class);
+			if (reflectiveAnnotation.getDistance() > 0) {
+				RuntimeHintsUtils.registerAnnotation(hints, reflectiveAnnotation.getRoot());
+			}
+		}
+
+	}
+
+}

spring-context/src/main/resources/META-INF/spring/aot.factories

@@ -0,0 +1,2 @@
+org.springframework.beans.factory.aot.BeanRegistrationAotProcessor= \
+org.springframework.context.aot.ReflectiveProcessorBeanRegistrationAotProcessor

spring-context/src/test/java/org/springframework/context/aot/ReflectiveProcessorBeanRegistrationAotProcessorTests.java

@@ -0,0 +1,220 @@
+/*
+ * Copyright 2002-2022 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.context.aot;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.aot.generate.DefaultGenerationContext;
+import org.springframework.aot.generate.GenerationContext;
+import org.springframework.aot.generate.InMemoryGeneratedFiles;
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.TypeReference;
+import org.springframework.aot.hint.annotation.Reflective;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationCode;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.beans.factory.support.RootBeanDefinition;
+import org.springframework.core.annotation.AliasFor;
+import org.springframework.core.annotation.SynthesizedAnnotation;
+import org.springframework.lang.Nullable;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link ReflectiveProcessorBeanRegistrationAotProcessor}.
+ *
+ * @author Stephane Nicoll
+ */
+class ReflectiveProcessorBeanRegistrationAotProcessorTests {
+
+	private final ReflectiveProcessorBeanRegistrationAotProcessor processor = new ReflectiveProcessorBeanRegistrationAotProcessor();
+
+	private final GenerationContext generationContext = new DefaultGenerationContext(
+			new InMemoryGeneratedFiles());
+
+	@Test
+	void shouldIgnoreNonAnnotatedType() {
+		assertThat(createContribution(String.class)).isNull();
+	}
+
+	@Test
+	void shouldProcessAnnotationOnType() {
+		process(SampleTypeAnnotatedBean.class);
+		assertThat(this.generationContext.getRuntimeHints().reflection().getTypeHint(SampleTypeAnnotatedBean.class))
+				.isNotNull();
+	}
+
+	@Test
+	void shouldProcessAnnotationOnConstructor() {
+		process(SampleConstructorAnnotatedBean.class);
+		assertThat(this.generationContext.getRuntimeHints().reflection().getTypeHint(SampleConstructorAnnotatedBean.class))
+				.satisfies(typeHint -> assertThat(typeHint.constructors()).singleElement()
+						.satisfies(constructorHint -> assertThat(constructorHint.getParameterTypes())
+								.containsExactly(TypeReference.of(String.class))));
+	}
+
+	@Test
+	void shouldProcessAnnotationOnField() {
+		process(SampleFieldAnnotatedBean.class);
+		assertThat(this.generationContext.getRuntimeHints().reflection().getTypeHint(SampleFieldAnnotatedBean.class))
+				.satisfies(typeHint -> assertThat(typeHint.fields()).singleElement()
+						.satisfies(fieldHint -> assertThat(fieldHint.getName()).isEqualTo("managed")));
+	}
+
+	@Test
+	void shouldProcessAnnotationOnMethod() {
+		process(SampleMethodAnnotatedBean.class);
+		assertThat(this.generationContext.getRuntimeHints().reflection().getTypeHint(SampleMethodAnnotatedBean.class))
+				.satisfies(typeHint -> assertThat(typeHint.methods()).singleElement()
+						.satisfies(methodHint -> assertThat(methodHint.getName()).isEqualTo("managed")));
+	}
+
+	@Test
+	void shouldRegisterAnnotation() {
+		process(SampleMethodMetaAnnotatedBean.class);
+		RuntimeHints runtimeHints = this.generationContext.getRuntimeHints();
+		assertThat(runtimeHints.reflection().getTypeHint(SampleInvoker.class)).satisfies(typeHint ->
+				assertThat(typeHint.getMemberCategories()).containsOnly(MemberCategory.INVOKE_PUBLIC_METHODS));
+		assertThat(runtimeHints.proxies().jdkProxies()).isEmpty();
+	}
+
+	@Test
+	void shouldRegisterAnnotationAndProxyWithAliasFor() {
+		process(SampleMethodMetaAnnotatedBeanWithAlias.class);
+		RuntimeHints runtimeHints = this.generationContext.getRuntimeHints();
+		assertThat(runtimeHints.reflection().getTypeHint(RetryInvoker.class)).satisfies(typeHint ->
+				assertThat(typeHint.getMemberCategories()).containsOnly(MemberCategory.INVOKE_PUBLIC_METHODS));
+		assertThat(runtimeHints.proxies().jdkProxies()).anySatisfy(jdkProxyHint ->
+				assertThat(jdkProxyHint.getProxiedInterfaces()).containsExactly(
+						TypeReference.of(RetryInvoker.class), TypeReference.of(SynthesizedAnnotation.class)));
+	}
+
+	@Nullable
+	private BeanRegistrationAotContribution createContribution(Class<?> beanClass) {
+		DefaultListableBeanFactory beanFactory = new DefaultListableBeanFactory();
+		beanFactory.registerBeanDefinition(beanClass.getName(), new RootBeanDefinition(beanClass));
+		return this.processor.processAheadOfTime(RegisteredBean.of(beanFactory, beanClass.getName()));
+	}
+
+	private void process(Class<?> beanClass) {
+		BeanRegistrationAotContribution contribution = createContribution(beanClass);
+		assertThat(contribution).isNotNull();
+		contribution.applyTo(this.generationContext, mock(BeanRegistrationCode.class));
+	}
+
+	@Reflective
+	@SuppressWarnings("unused")
+	static class SampleTypeAnnotatedBean {
+
+		private String notManaged;
+
+		public void notManaged() {
+
+		}
+	}
+
+	@SuppressWarnings("unused")
+	static class SampleConstructorAnnotatedBean {
+
+		@Reflective
+		SampleConstructorAnnotatedBean(String name) {
+
+		}
+
+		SampleConstructorAnnotatedBean(Integer nameAsNumber) {
+
+		}
+
+	}
+
+	@SuppressWarnings("unused")
+	static class SampleFieldAnnotatedBean {
+
+		@Reflective
+		String managed;
+
+		String notManaged;
+
+	}
+
+	@SuppressWarnings("unused")
+	static class SampleMethodAnnotatedBean {
+
+		@Reflective
+		void managed() {
+		}
+
+		void notManaged() {
+		}
+
+	}
+
+	@SuppressWarnings("unused")
+	static class SampleMethodMetaAnnotatedBean {
+
+		@SampleInvoker
+		void invoke() {
+		}
+
+		void notManaged() {
+		}
+
+	}
+
+	@SuppressWarnings("unused")
+	static class SampleMethodMetaAnnotatedBeanWithAlias {
+
+		@RetryInvoker
+		void invoke() {
+		}
+
+		void notManaged() {
+		}
+
+	}
+
+	@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+	@Retention(RetentionPolicy.RUNTIME)
+	@Documented
+	@Reflective
+	@interface SampleInvoker {
+
+		int retries() default 0;
+
+	}
+
+	@Target({ ElementType.METHOD })
+	@Retention(RetentionPolicy.RUNTIME)
+	@Documented
+	@SampleInvoker
+	@interface RetryInvoker {
+
+		@AliasFor(attribute = "retries", annotation = SampleInvoker.class)
+		int value() default 1;
+
+	}
+
+}

spring-core/src/main/java/org/springframework/aot/hint/annotation/Reflective.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2002-2022 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.aot.hint.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import org.springframework.core.annotation.AliasFor;
+
+/**
+ * Indicate that the annotated element requires reflection.
+ *
+ * <p>When present, either directly or as a meta-annotation, this annotation
+ * triggers the configured {@linkplain ReflectiveProcessor processors} against
+ * the annotated element. By default, a reflection hint is added on the
+ * annotated element so that it can be discovered and invoked if necessary.
+ *
+ * @author Stephane Nicoll
+ * @since 6.0
+ * @see SimpleReflectiveProcessor
+ */
+@Target({ ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.CONSTRUCTOR,
+		ElementType.FIELD, ElementType.METHOD })
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface Reflective {
+
+	/**
+	 * Alias for {@link #processors()}.
+	 */
+	Class<? extends ReflectiveProcessor>[] value() default SimpleReflectiveProcessor.class;
+
+	/**
+	 * {@link ReflectiveProcessor} implementations to invoke against the
+	 * annotated element.
+	 */
+	@AliasFor("value")
+	Class<? extends ReflectiveProcessor>[] processors() default SimpleReflectiveProcessor.class;
+
+}

spring-core/src/main/java/org/springframework/aot/hint/annotation/ReflectiveProcessor.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2002-2022 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.aot.hint.annotation;
+
+import java.lang.reflect.AnnotatedElement;
+
+import org.springframework.aot.hint.ReflectionHints;
+
+/**
+ * Process an {@link AnnotatedElement} and register the necessary reflection
+ * hints for it.
+ *
+ * @author Stephane Nicoll
+ * @since 6.0
+ */
+public interface ReflectiveProcessor {
+
+	/**
+	 * Register {@link ReflectionHints} against the specified {@link AnnotatedElement}.
+	 * @param hints the reflection hints instance to use
+	 * @param element the element to process
+	 */
+	void registerReflectionHints(ReflectionHints hints, AnnotatedElement element);
+
+}

spring-core/src/main/java/org/springframework/aot/hint/annotation/SimpleReflectiveProcessor.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2002-2022 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.aot.hint.annotation;
+
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.function.Consumer;
+
+import org.springframework.aot.hint.ExecutableHint.Builder;
+import org.springframework.aot.hint.ExecutableMode;
+import org.springframework.aot.hint.ReflectionHints;
+
+/**
+ * A simple {@link ReflectiveProcessor} implementation that registers only a
+ * reflection hint for the annotated type. Can be sub-classed to customize
+ * processing for a given {@link AnnotatedElement} type.
+ *
+ * @author Stephane Nicoll
+ * @since 6.0
+ */
+public class SimpleReflectiveProcessor implements ReflectiveProcessor {
+
+	private static final Consumer<Builder> INVOKE_EXECUTABLE = hint -> hint.setModes(ExecutableMode.INVOKE);
+
+	@Override
+	public void registerReflectionHints(ReflectionHints hints, AnnotatedElement element) {
+		if (element instanceof Class<?> type) {
+			registerTypeHint(hints, type);
+		}
+		else if (element instanceof Constructor<?> constructor) {
+			registerConstructorHint(hints, constructor);
+		}
+		else if (element instanceof Field field) {
+			registerFieldHint(hints, field);
+		}
+		else if (element instanceof Method method) {
+			registerMethodHint(hints, method);
+		}
+	}
+
+	/**
+	 * Register {@link ReflectionHints} against the specified {@link Class}.
+	 * @param hints the reflection hints instance to use
+	 * @param type the class to process
+	 */
+	protected void registerTypeHint(ReflectionHints hints, Class<?> type) {
+		hints.registerType(type, hint -> {});
+	}
+
+	/**
+	 * Register {@link ReflectionHints} against the specified {@link Constructor}.
+	 * @param hints the reflection hints instance to use
+	 * @param constructor the constructor to process
+	 */
+	protected void registerConstructorHint(ReflectionHints hints, Constructor<?> constructor) {
+		hints.registerConstructor(constructor, INVOKE_EXECUTABLE);
+	}
+
+	/**
+	 * Register {@link ReflectionHints} against the specified {@link Field}.
+	 * @param hints the reflection hints instance to use
+	 * @param field the field to process
+	 */
+	protected void registerFieldHint(ReflectionHints hints, Field field) {
+		hints.registerField(field);
+	}
+
+	/**
+	 * Register {@link ReflectionHints} against the specified {@link Method}.
+	 * @param hints the reflection hints instance to use
+	 * @param method the method to process
+	 */
+	protected void registerMethodHint(ReflectionHints hints, Method method) {
+		hints.registerMethod(method, INVOKE_EXECUTABLE);
+	}
+
+}

spring-core/src/main/java/org/springframework/aot/hint/annotation/package-info.java

@@ -0,0 +1,9 @@
+/**
+ * Annotation support for runtime hints.
+ */
+@NonNullApi
+@NonNullFields
+package org.springframework.aot.hint.annotation;
+
+import org.springframework.lang.NonNullApi;
+import org.springframework.lang.NonNullFields;

spring-core/src/test/java/org/springframework/aot/hint/annotation/SimpleReflectiveProcessorTests.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright 2002-2022 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.aot.hint.annotation;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.aot.hint.ExecutableMode;
+import org.springframework.aot.hint.ReflectionHints;
+import org.springframework.aot.hint.TypeReference;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link SimpleReflectiveProcessor}.
+ *
+ * @author Stephane Nicoll
+ */
+class SimpleReflectiveProcessorTests {
+
+	private final SimpleReflectiveProcessor processor = new SimpleReflectiveProcessor();
+
+	private final ReflectionHints hints = new ReflectionHints();
+
+	@Test
+	void registerReflectiveHintsForClass() {
+		processor.registerReflectionHints(hints, SampleBean.class);
+		assertThat(hints.typeHints()).singleElement().satisfies(typeHint -> {
+			assertThat(typeHint.getType()).isEqualTo(TypeReference.of(SampleBean.class));
+			assertThat(typeHint.getMemberCategories()).isEmpty();
+			assertThat(typeHint.constructors()).isEmpty();
+			assertThat(typeHint.fields()).isEmpty();
+			assertThat(typeHint.methods()).isEmpty();
+		});
+	}
+
+	@Test
+	void registerReflectiveHintsForConstructor() {
+		Constructor<?> constructor = SampleBean.class.getDeclaredConstructors()[0];
+		processor.registerReflectionHints(hints, constructor);
+		assertThat(hints.typeHints()).singleElement().satisfies(typeHint -> {
+			assertThat(typeHint.getType()).isEqualTo(TypeReference.of(SampleBean.class));
+			assertThat(typeHint.getMemberCategories()).isEmpty();
+			assertThat(typeHint.constructors()).singleElement().satisfies(constructorHint -> {
+				assertThat(constructorHint.getName()).isEqualTo("<init>");
+				assertThat(constructorHint.getModes()).containsExactly(ExecutableMode.INVOKE);
+				assertThat(constructorHint.getParameterTypes()).containsExactly(TypeReference.of(String.class));
+			});
+			assertThat(typeHint.fields()).isEmpty();
+			assertThat(typeHint.methods()).isEmpty();
+		});
+	}
+
+	@Test
+	void registerReflectiveHintsForField() throws NoSuchFieldException {
+		Field field = SampleBean.class.getDeclaredField("name");
+		processor.registerReflectionHints(hints, field);
+		assertThat(hints.typeHints()).singleElement().satisfies(typeHint -> {
+			assertThat(typeHint.getType()).isEqualTo(TypeReference.of(SampleBean.class));
+			assertThat(typeHint.getMemberCategories()).isEmpty();
+			assertThat(typeHint.constructors()).isEmpty();
+			assertThat(typeHint.fields()).singleElement().satisfies(fieldHint ->
+					assertThat(fieldHint.getName()).isEqualTo("name"));
+			assertThat(typeHint.methods()).isEmpty();
+		});
+	}
+
+	@Test
+	void registerReflectiveHintsForMethod() throws NoSuchMethodException {
+		Method method = SampleBean.class.getDeclaredMethod("setName", String.class);
+		processor.registerReflectionHints(hints, method);
+		assertThat(hints.typeHints()).singleElement().satisfies(typeHint -> {
+			assertThat(typeHint.getType()).isEqualTo(TypeReference.of(SampleBean.class));
+			assertThat(typeHint.getMemberCategories()).isEmpty();
+			assertThat(typeHint.constructors()).isEmpty();
+			assertThat(typeHint.fields()).isEmpty();
+			assertThat(typeHint.methods()).singleElement().satisfies(methodHint -> {
+				assertThat(methodHint.getName()).isEqualTo("setName");
+				assertThat(methodHint.getModes()).containsExactly(ExecutableMode.INVOKE);
+				assertThat(methodHint.getParameterTypes()).containsExactly(TypeReference.of(String.class));
+			});
+		});
+	}
+
+	static class SampleBean {
+
+		private String name;
+
+		SampleBean(String name) {
+			this.name = name;
+		}
+
+		public void setName(String name) {
+			this.name = name;
+		}
+	}
+
+}