Class Required

  • All Implemented Interfaces:
    Validator<java.lang.Void,​java.lang.Object>

    public final class Required
    extends AbstractValidator<java.lang.Void,​java.lang.Object>
    A validator that enforces that the value is not null and not the empty string. This validator is not configurable.
    • Method Detail

      • validate

        public void validate​(Field field,
                             java.lang.Void constraintValue,
                             MessageFormatter formatter,
                             java.lang.Object value)
                      throws ValidationException
        Description copied from interface: Validator
        Invoked after the client-submitted value has been translated to check that the value conforms to expectations (often, in terms of minimum or maximum value). If and only if the value is approved by all Validators is the value applied by the field.
        Parameters:
        field - the field for which a client submitted value is being validated
        constraintValue - the value used to constrain
        formatter - Validation messages, in the appropriate locale
        value - the translated value supplied by the user
        Throws:
        ValidationException - if the value violates the constraint
      • render

        public void render​(Field field,
                           java.lang.Void constraintValue,
                           MessageFormatter formatter,
                           MarkupWriter writer,
                           FormSupport formSupport)
        Description copied from interface: Validator
        Hook used by components to allow the validator to contribute additional attributes or (more often) client-side JavaScript (via the FormSupport.addValidation(Field, String, String, Object)).
        Parameters:
        field - the field which is currently being rendered
        constraintValue - the value used to constrain input
        formatter - validation message, in the appropriate locale
        writer - markup writer, allowing additional attributes to be written into the active element
        formSupport - used to add JavaScript