java.lang.ClassCastException: org.restlet.engine.http.HttpRequest cannot be cast to javax.servlet.http.HttpServletRequest

public class MyFilter extends Filter {

    @Override
    protected int beforeHandle(Request request, Response response) {

        int result = STOP;

        HttpServletRequest httpReq = (HttpServletRequest) request;
        String user_token = httpReq.getHeader("auth");

        if(user_token.equals("xyz")) {
            result = CONTINUE;
        }

        return result;
    }
}

Form headers = (Form) request.getAttributes().get("org.restlet.http.headers");
String user_token = headers.getFirstValue("Location");

getResponse().setLocationRef("http://...");

Series<Header> headers = (Series<Header>) getRequestAttributes().get("org.restlet.http.headers");
 String auth = headers.getFirstValue("auth");

Form headers = (Form) getRequestAttributes().get("org.restlet.http.headers");

String hID = headers.getFirstValue("Location");

Series headers = (Series) getRequestAttributes().get("org.restlet.http.headers");
String origin = headers.getFirstValue("Origin");`