code: protected ResponseBuilder createBadRequestResponse(Set<ConstraintViolation<?>> violations) {
          final Map<String, String> responseObj = violations.stream()
                  .collect(Collectors.toMap(v -> v.getPropertyPath().toString(), ConstraintViolation::getMessage));
  
          return Response.status(Response.Status.BAD_REQUEST)
                             .entity(responseObj);
      }
docs: Helper function to create a 400 Bad Request response, containing a JSON map giving details about the violations
  
  @param violations set of occurred constraint violations
  @return 400 Bad Request response, containing details on the constraint violations