internal val delegate: RealConnectionPool,
) {
  internal constructor(
    maxIdleConnections: Int = 5,
    keepAliveDuration: Long = 5,
    timeUnit: TimeUnit = TimeUnit.MINUTES,
    taskRunner: TaskRunner = TaskRunner.INSTANCE,
    connectionListener: ConnectionListener = ConnectionListener.NONE,
    readTimeoutMillis: Int = 10_000,
    writeTimeoutMillis: Int = 10_000,
    socketConnectTimeoutMillis: Int = 10_000,

  companion object {
    /**
     * A DNS that uses [InetAddress.getAllByName] to ask the underlying operating system to
     * lookup IP addresses. Most custom [Dns] implementations should delegate to this instance.
     */
    @JvmField
    val SYSTEM: Dns = DnsSystem()

    private class DnsSystem : Dns {
      override fun lookup(hostname: String): List<InetAddress> {
        try {

    }
  }

  /**
   * Remove and return the next event from the recorded sequence.
   *
   * @param eventClass a class to assert that the returned event is an instance of, or null to
   *     take any event class.
   * @param elapsedMs the time in milliseconds elapsed since the immediately-preceding event, or
   *     -1L to take any duration.
   */
  fun takeEvent(

import okhttp3.Request;
import okhttp3.Response;
import okhttp3.WebSocketListener;
import okio.ByteString;

/**
 * API access to the <a href="https://api.slack.com/apps">Slack API</a> as an application. One
 * instance of this class may operate without a user, or on behalf of many users. Use the Slack API
 * dashboard to create a client ID and secret for this application.
 *

3. Verify that the expected requests were made.

Here's a complete example:

```java
public void test() throws Exception {
  // Create a MockWebServer. These are lean enough that you can create a new
  // instance for every unit test.
  MockWebServer server = new MockWebServer();

  // Schedule some responses.
  server.enqueue(new MockResponse().setBody("hello, world!"));
  server.enqueue(new MockResponse().setBody("sup, bra?"));

      }
    }
  }

  private fun readAndWriteFrames() {
    check(socket == null)
    val socket = serverSocket!!.accept()!!
    this.socket = socket

    // Bail out now if this instance was closed while waiting for the socket to accept.
    synchronized(this) {
      if (executor.isShutdown) {
        socket.close()
        return
      }
    }
    val outputStream = socket.getOutputStream()

the preceding example we used a field, `callStartNanos`, to track the elapsed time of each event. This is handy, but it won’t work if multiple calls are executing concurrently. To accommodate this, use a `Factory` to create a new `EventListener` instance for each `Call`. This allows each listener to keep call-specific state.

This [sample factory](https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PrintEvents.java) creates a unique ID for each call...

 *  Fix: Don't crash on HTTP/2 HEAD requests when the `Content-Length` header is present but is not
    consistent with the length of the response body.

 *  Fix: Don't crash when converting a `HttpUrl` instance with an unresolvable hostname to a URI.
    The new behavior strips invalid characters like `"` and `{` from the hostname before converting.

 *
 * Specifically while junit instances passes into test constructor
 * are typically shares amongst all tests, a fresh instance will be
 * received here. Use with @BeforeAll and @AfterAll, is not supported.
 *
 * There are 3 ids for instances
 * - The test instance default (passed into constructor)
 * - The test lifecycle default (passed into test method, plus @BeforeEach, @AfterEach)

must choose to return Brotli responses.  n.b. It is not used for
sending requests.

```java
OkHttpClient client = new OkHttpClient.Builder()
  .addInterceptor(BrotliInterceptor.INSTANCE)
  .build();
```

```kotlin
implementation("com.squareup.okhttp3:okhttp-brotli:4.12.0")
```