.socketFactory(new UnixDomainSocketFactory(socketFile))
        .protocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE))
        .build();

    Request request = new Request.Builder()
        .url("http://publicobject.com/helloworld.txt")
        .build();

    try (Response response = client.newCall(request).execute()) {
      System.out.println(response.body().string());
    }

    server.shutdown();