.url("https://publicobject.com/helloworld.txt")
        .build();

    try (Response response = client.newCall(request).execute()) {
      if (!response.isSuccessful()) {
        Headers responseHeaders = response.headers();
        for (int i = 0; i < responseHeaders.size(); i++) {
          System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
        }

        .build();

    try (Response response = client.newCall(request).execute()) {
      if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

      Headers responseHeaders = response.headers();
      for (int i = 0; i < responseHeaders.size(); i++) {
        System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
      }

      System.out.println(response.body().string());

      logger.info(String.format("Sending request %s on %s%n%s",
          request.url(), chain.connection(), request.headers()));
      Response response = chain.proceed(request);

      long t2 = System.nanoTime();
      logger.info(String.format("Received response for %s in %.1fms%n%s",
          request.url(), (t2 - t1) / 1e6d, response.headers()));
      return response;
    }
  }

  public static void main(String... args) throws Exception {

    @Override public Response intercept(Chain chain) throws IOException {
      Request request = chain.request();
      Headers newHeaders = request.headers()
          .newBuilder()
          .add("Date", new Date())
          .build();
      Request newRequest = request.newBuilder()
          .headers(newHeaders)
          .build();
      return chain.proceed(newRequest);
    }
  }

        try (ResponseBody responseBody = response.body()) {
          if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

          Headers responseHeaders = response.headers();
          for (int i = 0, size = responseHeaders.size(); i < size; i++) {
            System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
          }

  public void run() throws Exception {
    Request request = new Request.Builder()
        .url("https://api.github.com/repos/square/okhttp/issues")
        .header("User-Agent", "OkHttp Headers.java")
        .addHeader("Accept", "application/json; q=0.5")
        .addHeader("Accept", "application/vnd.github.v3+json")
        .build();

    try (Response response = client.newCall(request).execute()) {