Add runtime hints for ReactorClientHttpRequestFactory

See gh-42587

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/client/ClientHttpRequestFactoriesRuntimeHints.java

@@ -29,6 +29,7 @@ import org.springframework.http.client.AbstractClientHttpRequestFactoryWrapper;
 import org.springframework.http.client.ClientHttpRequestFactory;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.http.client.JettyClientHttpRequestFactory;
+import org.springframework.http.client.ReactorClientHttpRequestFactory;
 import org.springframework.http.client.SimpleClientHttpRequestFactory;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
@@ -63,6 +64,10 @@ class ClientHttpRequestFactoriesRuntimeHints implements RuntimeHintsRegistrar {
 			typeHint.onReachableType(HttpURLConnection.class);
 			registerReflectionHints(hints, SimpleClientHttpRequestFactory.class);
 		});
+		hints.registerTypeIfPresent(classLoader, ClientHttpRequestFactories.REACTOR_CLIENT_CLASS, (typeHint) -> {
+			typeHint.onReachableType(TypeReference.of(ClientHttpRequestFactories.REACTOR_CLIENT_CLASS));
+			registerReflectionHints(hints, ReactorClientHttpRequestFactory.class, long.class);
+		});
 	}
 
 	private void registerReflectionHints(ReflectionHints hints,

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/client/ClientHttpRequestFactoriesRuntimeHintsTests.java

@@ -27,6 +27,7 @@ import org.springframework.aot.hint.predicate.RuntimeHintsPredicates;
 import org.springframework.http.client.AbstractClientHttpRequestFactoryWrapper;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.http.client.JettyClientHttpRequestFactory;
+import org.springframework.http.client.ReactorClientHttpRequestFactory;
 import org.springframework.http.client.SimpleClientHttpRequestFactory;
 import org.springframework.util.ReflectionUtils;
 
@@ -72,6 +73,17 @@ class ClientHttpRequestFactoriesRuntimeHintsTests {
 			.accepts(hints);
 	}
 
+	@Test
+	void shouldRegisterReactorHints() {
+		RuntimeHints hints = new RuntimeHints();
+		new ClientHttpRequestFactoriesRuntimeHints().registerHints(hints, getClass().getClassLoader());
+		ReflectionHintsPredicates reflection = RuntimeHintsPredicates.reflection();
+		assertThat(reflection.onMethod(method(ReactorClientHttpRequestFactory.class, "setConnectTimeout", int.class)))
+			.accepts(hints);
+		assertThat(reflection.onMethod(method(ReactorClientHttpRequestFactory.class, "setReadTimeout", long.class)))
+			.accepts(hints);
+	}
+
 	@Test
 	void shouldRegisterSimpleHttpHints() {
 		RuntimeHints hints = new RuntimeHints();