How to add custom OAuth approval page to 'Spring Boot OAuth2 Identity Server'

Question

@Controller
@SessionAttributes(types = AuthorizationRequest.class)
public class WhiteLableController {

    @RequestMapping("/oauth/confirm_access")
    public String getAccessConfirmation() throws Exception {
        return "access_confirmation";
    }
}

when I keep the access_confirmation.html in 'public' or 'static' folders in spring boot its not working. Could someone help me on this ?

404 Error Page :

Whitelabel Error Page

This application has no explicit mapping for /error, so you are seeing this as a fallback.

Fri Aug 18 14:11:19 CEST 2017
There was an unexpected error (type=Not Found, status=404).
No message available