public class WindupWizard implements UIWizard, UICommand

    @Inject
    @WithAttributes(label = "Input", required = true, description = "Input File or Directory (a Directory is required for source mode)")
    private UIInput<FileResource<?>> input;

    @Override
    public void validate(UIValidationContext context)
    {
        FileResource<?> inputValue = this.input.getValue();
        File inputFile = inputValue.getUnderlyingResourceObject();

[Desktop]$ windup-migrate-app 
Exception when parsing/running: windup-migrate-app , null
[Desktop]$