Review usage of BindingReflectionHintsRegistrar#registerReflectionHints

Closes gh-32753

Author: snicoll

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

@@ -62,7 +62,7 @@ public class BindingReflectionHintsRegistrar {
 	 * @param hints the hints instance to use
 	 * @param types the types to register
 	 */
-	public void registerReflectionHints(ReflectionHints hints, @Nullable Type... types) {
+	public void registerReflectionHints(ReflectionHints hints, Type... types) {
 		Set<Type> seen = new LinkedHashSet<>();
 		for (Type type : types) {
 			registerReflectionHints(hints, seen, type);

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/MessageMappingReflectiveProcessor.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.
@@ -83,7 +83,10 @@ protected void registerParameterHints(ReflectionHints hints, Method method) {
 		for (Parameter parameter : method.getParameters()) {
 			MethodParameter methodParameter = MethodParameter.forParameter(parameter);
 			if (Message.class.isAssignableFrom(methodParameter.getParameterType())) {
-				this.bindingRegistrar.registerReflectionHints(hints, getMessageType(methodParameter));
+				Type messageType = getMessageType(methodParameter);
+				if (messageType != null) {
+					this.bindingRegistrar.registerReflectionHints(hints, messageType);
+				}
 			}
 			else if (couldBePayload(methodParameter)) {
 				this.bindingRegistrar.registerReflectionHints(hints, methodParameter.getGenericParameterType());

spring-web/src/main/java/org/springframework/web/bind/annotation/ControllerMappingReflectiveProcessor.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.
@@ -84,7 +84,10 @@ protected void registerParameterTypeHints(ReflectionHints hints, MethodParameter
 			this.bindingRegistrar.registerReflectionHints(hints, methodParameter.getGenericParameterType());
 		}
 		else if (HttpEntity.class.isAssignableFrom(methodParameter.getParameterType())) {
-			this.bindingRegistrar.registerReflectionHints(hints, getHttpEntityType(methodParameter));
+			Type httpEntityType = getHttpEntityType(methodParameter);
+			if (httpEntityType != null) {
+				this.bindingRegistrar.registerReflectionHints(hints, httpEntityType);
+			}
 		}
 	}
 
@@ -94,7 +97,10 @@ protected void registerReturnTypeHints(ReflectionHints hints, MethodParameter re
 			this.bindingRegistrar.registerReflectionHints(hints, returnTypeParameter.getGenericParameterType());
 		}
 		else if (HttpEntity.class.isAssignableFrom(returnTypeParameter.getParameterType())) {
-			this.bindingRegistrar.registerReflectionHints(hints, getHttpEntityType(returnTypeParameter));
+			Type httpEntityType = getHttpEntityType(returnTypeParameter);
+			if (httpEntityType != null) {
+				this.bindingRegistrar.registerReflectionHints(hints, httpEntityType);
+			}
 		}
 	}