Add HandshakeWebSocketService runtime hints

Closes gh-29146

spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/support/HandshakeWebSocketService.java

@@ -114,7 +114,7 @@ public HandshakeWebSocketService(RequestUpgradeStrategy upgradeStrategy) {
 		this.upgradeStrategy = upgradeStrategy;
 	}
 
-	private static RequestUpgradeStrategy initUpgradeStrategy() {
+	static RequestUpgradeStrategy initUpgradeStrategy() {
 		String className;
 		if (tomcatPresent) {
 			className = "TomcatRequestUpgradeStrategy";

spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/support/HandshakeWebSocketServiceRuntimeHints.java

@@ -0,0 +1,37 @@
+/*
+ * 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.reactive.socket.server.support;
+
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.RuntimeHintsRegistrar;
+
+/**
+ * {@link RuntimeHintsRegistrar} implementation that registers reflection hints related to
+ * {@link HandshakeWebSocketService}.
+ *
+ * @author Sebastien Deleuze
+ * @since 6.0
+ */
+class HandshakeWebSocketServiceRuntimeHints implements RuntimeHintsRegistrar {
+
+	@Override
+	public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
+		hints.reflection().registerType(HandshakeWebSocketService.initUpgradeStrategy().getClass(),
+				MemberCategory.INVOKE_DECLARED_CONSTRUCTORS);
+	}
+}

spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/support/WebSocketHandlerAdapter.java

@@ -18,6 +18,7 @@
 
 import reactor.core.publisher.Mono;
 
+import org.springframework.context.annotation.ImportRuntimeHints;
 import org.springframework.core.Ordered;
 import org.springframework.util.Assert;
 import org.springframework.web.reactive.HandlerAdapter;
@@ -45,6 +46,7 @@
  * @author Rossen Stoyanchev
  * @since 5.0
  */
+@ImportRuntimeHints(HandshakeWebSocketServiceRuntimeHints.class)
 public class WebSocketHandlerAdapter implements HandlerAdapter, Ordered {
 
 	private final WebSocketService webSocketService;