customize binding request parameters and fileds inside the accepted to controller method bean in spring mvc

I have the following class:

public class MyDTO { 
       @NotEmpty      
       private String isKiosk;
       ...
}

and following url:

http://localhost:1234/mvc/controllerUrl?isKiosk=false

and following controller method:

@RequestMapping(method = RequestMethod.GET, produces = APPLICATION_JSON)
@ResponseBody
public ResponseEntity<List<?>> getRequestSupportKludge(@Valid final MyDTO myDTO, BindingResult bindingResult) {
    ...
}

When I stop in debug at getRequestSupportKludge method I see that myDTO.isKiosk equals null.

I cannot change the request url.

Where can I configure mapping for my request parameter ?

it is working after adding following binder:

@InitBinder
public void initBinder(WebDataBinder binder) {
    binder.registerCustomEditor(String.class, "isKiosk", new PropertyEditorSupport() {
        public void setAsText(String name) {
            setValue(name);
        }
    });
}