diff --git a/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java b/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
index fa84da293db0..3b69ff38e472 100644
--- a/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
+++ b/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
@@ -33,7 +33,6 @@
 import kotlin.reflect.full.KClassifiers;
 import kotlin.reflect.full.KTypes;
 import kotlin.reflect.jvm.KCallablesJvm;
-import kotlin.reflect.jvm.KTypesJvm;
 import kotlin.reflect.jvm.ReflectJvmMapping;
 import kotlinx.coroutines.BuildersKt;
 import kotlinx.coroutines.CoroutineStart;
@@ -109,7 +108,7 @@ public static Publisher<?> invokeSuspendingFunction(Method method, Object target
 	 * @throws IllegalArgumentException if {@code method} is not a suspending function
 	 * @since 6.0
 	 */
-	@SuppressWarnings("deprecation")
+	@SuppressWarnings({"deprecation", "DataFlowIssue"})
 	public static Publisher<?> invokeSuspendingFunction(CoroutineContext context, Method method, Object target,
 			Object... args) {
 		Assert.isTrue(KotlinDetector.isSuspendingFunction(method), "'method' must be a suspending function");
@@ -128,7 +127,7 @@ public static Publisher<?> invokeSuspendingFunction(CoroutineContext context, Me
 								if (!(parameter.isOptional() && arg == null)) {
 									KType type = parameter.getType();
 									if (!(type.isMarkedNullable() && arg == null)) {
-										KClass<?> kClass = KTypesJvm.getJvmErasure(type);
+										KClass<?> kClass = (KClass<?>) type.getClassifier();
 										if (KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
 											arg = KClasses.getPrimaryConstructor(kClass).call(arg);
 										}
@@ -148,10 +147,10 @@ public static Publisher<?> invokeSuspendingFunction(CoroutineContext context, Me
 		if (KTypes.isSubtypeOf(returnType, flowType)) {
 			return mono.flatMapMany(CoroutinesUtils::asFlux);
 		}
-		else if (KTypes.isSubtypeOf(returnType, monoType)) {
-			return mono.flatMap(o -> ((Mono<?>)o));
-		}
-		else if (KTypes.isSubtypeOf(returnType, publisherType)) {
+		if (KTypes.isSubtypeOf(returnType, publisherType)) {
+			if (KTypes.isSubtypeOf(returnType, monoType)) {
+				return mono.flatMap(o -> ((Mono<?>)o));
+			}
 			return mono.flatMapMany(o -> ((Publisher<?>)o));
 		}
 		return mono;
diff --git a/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java b/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
index 918ce2226d7c..8bd593934ad6 100644
--- a/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
+++ b/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
@@ -29,7 +29,6 @@
 import kotlin.reflect.KType;
 import kotlin.reflect.full.KClasses;
 import kotlin.reflect.jvm.KCallablesJvm;
-import kotlin.reflect.jvm.KTypesJvm;
 import kotlin.reflect.jvm.ReflectJvmMapping;
 
 import org.springframework.context.MessageSource;
@@ -299,7 +298,7 @@ protected Object invokeSuspendingFunction(Method method, Object target, Object[]
 	private static class KotlinDelegate {
 
 		@Nullable
-		@SuppressWarnings("deprecation")
+		@SuppressWarnings({"deprecation", "DataFlowIssue"})
 		public static Object invokeFunction(Method method, Object target, Object[] args) throws InvocationTargetException, IllegalAccessException {
 			KFunction<?> function = ReflectJvmMapping.getKotlinFunction(method);
 			// For property accessors
@@ -319,7 +318,7 @@ public static Object invokeFunction(Method method, Object target, Object[] args)
 						if (!(parameter.isOptional() && arg == null)) {
 							KType type = parameter.getType();
 							if (!(type.isMarkedNullable() && arg == null)) {
-								KClass<?> kClass = KTypesJvm.getJvmErasure(type);
+								KClass<?> kClass = (KClass<?>) type.getClassifier();
 								if (KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
 									arg = KClasses.getPrimaryConstructor(kClass).call(arg);
 								}
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
index de362ea27a91..890d2979cb87 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
@@ -34,7 +34,6 @@
 import kotlin.reflect.KType;
 import kotlin.reflect.full.KClasses;
 import kotlin.reflect.jvm.KCallablesJvm;
-import kotlin.reflect.jvm.KTypesJvm;
 import kotlin.reflect.jvm.ReflectJvmMapping;
 import reactor.core.publisher.Mono;
 
@@ -298,7 +297,7 @@ private static class KotlinDelegate {
 		private static final String COROUTINE_CONTEXT_ATTRIBUTE = "org.springframework.web.server.CoWebFilter.context";
 
 		@Nullable
-		@SuppressWarnings("deprecation")
+		@SuppressWarnings({"deprecation", "DataFlowIssue"})
 		public static Object invokeFunction(Method method, Object target, Object[] args, boolean isSuspendingFunction,
 				ServerWebExchange exchange) throws InvocationTargetException, IllegalAccessException {
 
@@ -330,7 +329,7 @@ public static Object invokeFunction(Method method, Object target, Object[] args,
 							if (!(parameter.isOptional() && arg == null)) {
 								KType type = parameter.getType();
 								if (!(type.isMarkedNullable() && arg == null)) {
-									KClass<?> kClass = KTypesJvm.getJvmErasure(type);
+									KClass<?> kClass = (KClass<?>) type.getClassifier();
 									if (KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
 										arg = KClasses.getPrimaryConstructor(kClass).call(arg);
 									}