Question

I have a form which contain some radio button and check-boxes. Whenever user selects/deselects a radio button or check-box few other input fields are enabled/disabled.
I want to add validation only for fields which are enabled when user submits the form. Fields which are disabled at the time of submission should not be considered for validation.

I don’t want to add this in client side validation.Is there any better /easy way to implement conditional validation in Spring 3.0 instead of adding multiple if in validator ?

Thanks!

Answer 1

When fields are disabled they are transferred to controller as null. I wanted to add a validation which will allow either null i.e disabled field or not blank field i.e. enabled but empty field.
So I created a custom annotation NotBlankOrNull which will allow null and non empty strings also it takes care of blank spaces.
Here is my Annotation

@Documented
@Constraint(validatedBy = { NotBlankOrNullValidator.class })
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
public @interface NotBlankOrNull {
    String message() default "{org.hibernate.validator.constraints.NotBlankOrNull.message}";

    Class<?>[] groups() default { };

    Class<? extends Payload>[] payload() default { };
}

Validator class

public class NotBlankOrNullValidator implements ConstraintValidator<NotBlankOrNull, String> {

    public boolean isValid(String s, ConstraintValidatorContext constraintValidatorContext) {
        if ( s == null ) {
            return true;
        }
        return s.trim().length() > 0;
    }

    @Override
    public void initialize(NotBlankOrNull constraint) {

    }
} 

I have also updated more details on my site.