Interface ProfileValidator

Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface public interface ProfileValidator
Used to validate profiles and to apply acceptance rules. Bellow the example of usage :
 
 private static ProfileValidator checkDuplicateInDatabaseValidator() {
    return (profile, profileIdentifier) -> {
        GenericRejectionCause rejection = null;
        boolean exist = ... exists in database?;
        if (exist) {
           rejection = GenericRejectionCause.rejectDuplicatedInDatabase(profileIdentifier);
        }
        return (rejection == null) ? Optional.empty() : Optional.of(rejection);
    };
 }
 
 
The call the method like this to validate the profile p: GenericRejectionCause rejection = checkDuplicateInDatabaseValidator().validate(p, p.getName()); Check if rejection is present then do the resolution