```java
OkHttpClient client = new OkHttpClient();

String run(String url) throws IOException {
  Request request = new Request.Builder()
      .url(url)
      .build();

  try (Response response = client.newCall(request).execute()) {
    return response.body().string();
  }
}
```


Post to a Server
----------------

This program posts data to a service. [Full source][post_example].

```java

    val request =
      Request.Builder()
        .header("Authorization", "Client-ID $IMGUR_CLIENT_ID")
        .url("https://api.imgur.com/3/image")
        .post(requestBody)
        .build()

    client.newCall(request).execute().use { response ->
      if (!response.isSuccessful) throw IOException("Unexpected code $response")

      println(response.body.string())
    }
  }

  companion object {
    /**

            .build();
      } else {
        System.out.println("Force cache: false");
        clientForCall = client;
      }

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

        System.out.println("    Network: " + (response.networkResponse() != null));
        System.out.println();

        .build()

    // An example test URL that returns client certificate details.
    val request =
      Request.Builder()
        .url("https://prod.idrix.eu/secure/")
        .build()

    client.newCall(request).execute().use { response ->
      if (!response.isSuccessful) throw IOException("Unexpected code $response")

      println(response.body.string())
    }
  }
}

  ) {
    val request = buildRequest(hostname, type)
    val response = getCacheOnlyResponse(request)

    response?.let { processResponse(it, hostname, results, failures) } ?: networkRequests.add(
      client.newCall(request),
    )
  }

  private fun executeRequests(
    hostname: String,
    networkRequests: List<Call>,
    responses: MutableList<InetAddress>,
    failures: MutableList<Exception>,
  ) {

        .url("http://httpbin.org/delay/2") // This URL is served with a 2 second delay.
        .build();

    final long startNanos = System.nanoTime();
    final Call call = client.newCall(request);

    // Schedule a job to cancel the call in 1 second.
    executor.schedule(() -> {
      System.out.printf("%.2f Canceling call.%n", (System.nanoTime() - startNanos) / 1e9f);
      call.cancel();

    // Create request for remote resource.
    Request request = new Request.Builder()
        .url(ENDPOINT)
        .build();

    // Execute the request and retrieve the response.
    try (Response response = client.newCall(request).execute()) {
      // Deserialize HTTP response to concrete type.
      ResponseBody body = response.body();
      List<Contributor> contributors = CONTRIBUTORS_JSON_ADAPTER.fromJson(body.source());

        )
    }

    val client = clientBuilder.build()

    val request =
      Request.Builder()
        .url("https://valid-isrgrootx1.letsencrypt.org/robots.txt")
        .build()
    client.newCall(request).execute().use { response ->
      assertThat(response.code).isEqualTo(404)
      assertThat(response.protocol).isEqualTo(Protocol.HTTP_2)
    }
  }

    .build();

Request request = new Request.Builder()
    .url("http://www.publicobject.com/helloworld.txt")
    .header("User-Agent", "OkHttp Example")
    .build();

Response response = client.newCall(request).execute();
response.body().close();
```

  return s.equals("Content-Type", ignoreCase = true)
}

fun Main.commonRun() {
  client = createClient()
  val request = createRequest()

  try {
    val response = client!!.newCall(request).execute()
    if (showHeaders) {
      println(StatusLine.get(response))
      val headers = response.headers
      for ((name, value) in headers) {
        println("$name: $value")
      }
      println()