Register reflection hints for HttpExchange annotations

See gh-29271

spring-web/src/main/java/org/springframework/web/service/annotation/HttpExchange.java

@@ -22,6 +22,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.springframework.aot.hint.annotation.Reflective;
 import org.springframework.core.annotation.AliasFor;
 import org.springframework.web.bind.annotation.Mapping;
 
@@ -105,6 +106,7 @@ import org.springframework.web.bind.annotation.Mapping;
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @Mapping
+@Reflective(HttpExchangeReflectiveProcessor.class)
 public @interface HttpExchange {
 
 	/**

spring-web/src/main/java/org/springframework/web/service/annotation/HttpExchangeReflectiveProcessor.java

@@ -0,0 +1,70 @@
+/*
+ * 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.web.service.annotation;
+
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Method;
+import java.lang.reflect.Parameter;
+
+import org.springframework.aot.hint.BindingReflectionHintsRegistrar;
+import org.springframework.aot.hint.ExecutableMode;
+import org.springframework.aot.hint.ReflectionHints;
+import org.springframework.aot.hint.annotation.ReflectiveProcessor;
+import org.springframework.core.MethodParameter;
+import org.springframework.web.bind.annotation.RequestBody;
+
+/**
+ * {@link ReflectiveProcessor} implementation for {@link HttpExchange @HttpExchange}
+ * and annotated methods. On top of registering reflection hints for invoking
+ * the annotated method, this implementation handles reflection-based
+ * binding for return types and parameters annotated with {@link RequestBody}.
+ *
+ * @author Sebastien Deleuze
+ * @since 6.0
+ */
+class HttpExchangeReflectiveProcessor implements ReflectiveProcessor {
+
+	private final BindingReflectionHintsRegistrar bindingRegistrar = new BindingReflectionHintsRegistrar();
+
+	@Override
+	public void registerReflectionHints(ReflectionHints hints, AnnotatedElement element) {
+		if (element instanceof Method method) {
+			registerMethodHints(hints, method);
+		}
+	}
+
+	protected void registerMethodHints(ReflectionHints hints, Method method) {
+		hints.registerMethod(method, ExecutableMode.INVOKE);
+		for (Parameter parameter : method.getParameters()) {
+			registerParameterTypeHints(hints, MethodParameter.forParameter(parameter));
+		}
+		registerReturnTypeHints(hints, MethodParameter.forExecutable(method, -1));
+	}
+
+	protected void registerParameterTypeHints(ReflectionHints hints, MethodParameter methodParameter) {
+		if (methodParameter.hasParameterAnnotation(RequestBody.class)) {
+			this.bindingRegistrar.registerReflectionHints(hints, methodParameter.getGenericParameterType());
+		}
+	}
+
+	protected void registerReturnTypeHints(ReflectionHints hints, MethodParameter returnTypeParameter) {
+		if (!void.class.equals(returnTypeParameter.getParameterType())) {
+			this.bindingRegistrar.registerReflectionHints(hints, returnTypeParameter.getGenericParameterType());
+		}
+	}
+
+}

spring-web/src/test/java/org/springframework/web/service/annotation/HttpExchangeReflectiveProcessorTests.java

@@ -0,0 +1,102 @@
+/*
+ * 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.web.service.annotation;
+
+import java.lang.reflect.Method;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.predicate.RuntimeHintsPredicates;
+import org.springframework.web.bind.annotation.RequestBody;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link HttpExchangeReflectiveProcessor}.
+ *
+ * @author Sebastien Deleuze
+ */
+class HttpExchangeReflectiveProcessorTests {
+
+	private final HttpExchangeReflectiveProcessor processor = new HttpExchangeReflectiveProcessor();
+
+	private final RuntimeHints hints = new RuntimeHints();
+
+	@Test
+	void registerReflectiveHintsForMethodWithReturnValue() throws NoSuchMethodException {
+		Method method = SampleService.class.getDeclaredMethod("get");
+		processor.registerReflectionHints(hints.reflection(), method);
+		assertThat(RuntimeHintsPredicates.reflection().onType(SampleService.class)).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(SampleService.class, "get")).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onType(Response.class)).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(Response.class, "getMessage")).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(Response.class, "setMessage")).accepts(hints);
+	}
+
+	@Test
+	void registerReflectiveHintsForMethodWithRequestBodyParameter() throws NoSuchMethodException {
+		Method method = SampleService.class.getDeclaredMethod("post", Request.class);
+		processor.registerReflectionHints(hints.reflection(), method);
+		assertThat(RuntimeHintsPredicates.reflection().onType(SampleService.class)).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(SampleService.class, "post")).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onType(Request.class)).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(Request.class, "getMessage")).accepts(hints);
+		assertThat(RuntimeHintsPredicates.reflection().onMethod(Request.class, "setMessage")).accepts(hints);
+	}
+
+
+	interface SampleService {
+
+		@GetExchange
+		Response get();
+
+		@PostExchange
+		void post(@RequestBody Request request);
+	}
+
+	static class Request {
+
+		private String message;
+
+		public String getMessage() {
+			return message;
+		}
+
+		public void setMessage(String message) {
+			this.message = message;
+		}
+	}
+
+	static class Response {
+
+		private String message;
+
+		public Response(String message) {
+			this.message = message;
+		}
+
+		public String getMessage() {
+			return message;
+		}
+
+		public void setMessage(String message) {
+			this.message = message;
+		}
+	}
+
+}