RequestBuilder builder = new RequestBuilder();
            builder.setMethod(Method.CONNECT.getMethodString());
            builder.setUrl("http://" + getAuthority(requestUri));
            Request request = builder.build();
            AsyncHandler handler = new AsyncCompletionHandler() {
                @Override
                public Object onCompleted(Response response) throws Exception {
                    if (response.getStatusCode() != 200) {
                        PROXY_AUTH_FAILURE.set(ctx.getConnection(), Boolean.TRUE);
                    }