Quick fix in the logic to determine 'composed' flag

spring-cloud-function-context/src/main/java/org/springframework/cloud/function/context/catalog/BeanFactoryAwareFunctionRegistry.java

@@ -449,9 +449,11 @@ public class BeanFactoryAwareFunctionRegistry
 
 		FunctionInvocationWrapper(Object target, Type functionType, String functionDefinition, String... acceptedOutputMimeTypes) {
 			this.target = target;
-			this.composed = !target.getClass().getName().contains("$$EnhancerBySpringCGLIB")
+			this.composed = target instanceof RoutingFunction ||
+					(!target.getClass().getName().contains("$$EnhancerBySpringCGLIB")
 					&& !AopUtils.isAopProxy(target) && !AopUtils.isJdkDynamicProxy(target)
-					&& target.getClass().getDeclaredFields().length > 1;
+					&& target.getClass().getDeclaredFields().length > 1
+					&& target.getClass().isSynthetic());
 			this.functionType = functionType;
 			this.acceptedOutputMimeTypes = acceptedOutputMimeTypes;
 			this.functionDefinition = functionDefinition;