I’m using Sonarqube 9.2 and have enabled rule:
java:S3553 “Optional” should not be used for parameters
Now I get a false positive for this code snippet in spring rest controllers:
@GetMapping("/{id}")
ResponseEntity<Foo> getFoo(@PathVariable Long id, @RequestParam(value = "validation-scope") Optional<ValidationScope> validationScope, @RequestParam(value = "bar") Optional<UUID> bar) throws ValidationException;
Spring Framework documentation notes that for non mandatory parameters Optional can be used:
https://docs.spring.io/spring-framework/docs/5.3.14/reference/html/web.html#mvc-ann-requestparam
So I think this is a valid exception to the rule as spring mvc cares about it that the optional itself is not null.
Kind regards,
Michael