Now, having enough knowledge about the Spring Cloud Function ecosystem, we may get back on topic and see how to use this awesome module. There is an additional module called Spring Cloud Starter Stream App Function, which enables the use of Spring Cloud Function features in Spring Cloud Data Flow. This module allows us to use pure jars and deploy them as part of the Spring Cloud Data Flow without any redundant overhead from Spring Boot. Since we have a plain mapping here, a simplified Validation function can be reduced to a conventional Function<Payment, PaymentValidation> function and can look as follows:
public class PaymentValidator implements Function<Payment, Payment> { public Payment ...
