private var started = false

    fun server(name: String): MockWebServer {
      return servers.getOrPut(name) {
        MockWebServer().also {
          if (started) it.start()
        }
      }
    }

    fun startAll() {
      started = true
      for (server in servers.values) {
        server.start()
      }
    }

    fun shutdownAll() {
      try {

  fun beforeEach(server: MockWebServer) {
    instanceServer = server

    assertThat(instanceServer).isNotSameInstanceAs(staticServer)
    assertThat(instanceServer).isSameInstanceAs(server)

    assertThat(server.started).isTrue()
    server.enqueue(MockResponse())
  }

  @AfterEach
  fun afterEach(server: MockWebServer) {
    assertThat(server).isSameInstanceAs(instanceServer)
  }

  @Test

 * server may not have had time to close the socket. The socket will be closed at an indeterminate
 * point before or during the second request. It may be closed after client has started sending the
 * request body. If a request body is not retryable then the client may fail the request, making
 * client behavior non-deterministic. Add delays in the client to improve the chances that the

   *
   * The target execution time is implemented on a best-effort basis. If another task in this queue
   * is running when that time is reached, that task is allowed to complete before this task is
   * started. Similarly the task will be delayed if the host lacks compute resources.
   *
   * @throws RejectedExecutionException if the queue is shut down and the task is not cancelable.
   */
  fun schedule(
    task: Task,

#### Http2Connection

This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

 * Any IO - writing to files or network should be done asynchronously.
 */
@ExperimentalOkHttpApi
abstract class ConnectionListener {
  /**
   * Invoked as soon as a call causes a connection to be started.
   */
  open fun connectStart(
    route: Route,
    call: Call,
  ) {}

  /**
   * Invoked when a connection fails to be established.
   */
  open fun connectFailed(
    route: Route,

    currentTask = nextTask
    contextSwitchCount++
    nextTask.start()
    return nextTask
  }

  private interface SerialTask {
    /** Returns true if this task is ready to start. */
    fun isReady() = true

    /** Do this task's work, and then start another, such as by calling [startNextTask]. */
    fun start()
  }

  private object TestThreadSerialTask : SerialTask {

 * Prefer to alternate IP addresses from different address families, (IPv6 / IPv4), starting with IPv6.
 * Don't start a new attempt until 250 ms after the most recent attempt was started.
 * Keep whichever TCP connection succeeds first and cancel all the others.
 * Race TCP only. Only attempt a TLS handshake on the winning TCP connection.

            cancelAll()
          } finally {
            coordinatorWaiting = false
          }
        }
      }
    }
  }

  /** Start another thread, unless a new thread is already scheduled to start. */
  private fun startAnotherThread() {
    lock.assertHeld()
    if (executeCallCount > runCallCount) return // A thread is still starting.

    executeCallCount++

  private val factory = routePlanner.factory
  private val taskFaker = routePlanner.taskFaker
  private val peer = MockHttp2Peer()

  /** The fake task runner prevents the cleanup runnable from being started.  */
  private val addressA = factory.newAddress("a")
  private val routeA1 = factory.newRoute(addressA)
  private val addressB = factory.newAddress("b")
  private val routeB1 = factory.newRoute(addressB)