How to use jooby-hbv validation

Question

I want to use jooby validation I looked through https://jooby.org/doc/hbv/ but I can't use it

Answer 1

1. You need to initialise Hibernate Validator in the App class.

    use(new Hbv(ClassUtils.getClasses("com.package.of.classes.validate")));

2. Annotate your classes with the validators. Note these classes have to be in the above package. Example:

    public class SampleRequest {
        @NotNull
        private Long id;
        @NotBlank
        String name;
        private @NotBlank
        String description;
        private @Min(1)
        double amount;
    }

3. You can then use a general error handler in the App class.

     err((req, rsp, err) -> {
                Throwable cause = err.getCause();
                if (cause instanceof ConstraintViolationException) {
                    Set<ConstraintViolation<?>> constraints = ((ConstraintViolationException) cause)
                            .getConstraintViolations();

                    // handle errors, return error response 
                } else {
                   // ......
                }
            });

4. Or you can manually validate in your service:

    private void validateRequest(SampleRequest sampleRequest) {
            Validator validator = factory.getValidator();
            Set<ConstraintViolation<SampleRequest>> constraintViolations =
                    validator.validate(sampleRequest);
            if (!constraintViolations.isEmpty()) {
                StringBuilder builder = new StringBuilder();
                for (ConstraintViolation<SampleRequest> error : constraintViolations) {
                    logger.error(error.getPropertyPath() + "::" + error.getMessage());
                    builder.append(error.getPropertyPath() + "::" + error.getMessage());
                }
                throw new IllegalArgumentException(builder.toString());
            }
    }