if (deferredPlans.isNotEmpty()) return deferredPlans.removeFirst()

    // Do blocking calls to plan a route for a new connection.
    val connect = planConnect()

    // Now that we have a set of IP addresses, make another attempt at getting a connection from
    // the pool. We have a better chance of matching thanks to connection coalescing.
    val pooled2 = planReusePooledConnection(connect, connect.routes)

      // we allow one second worth of work to go in a burst (i.e. take less than a second)
      assertThat(burst).isAtMost(1000);
      long afterBurst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // but work beyond that must take at least one second
      assertThat(afterBurst).isAtLeast(1000);
    }
  }

  /**

      // we allow one second worth of work to go in a burst (i.e. take less than a second)
      assertThat(burst).isAtMost(1000);
      long afterBurst = measureTotalTimeMillis(limiter, oneSecWorthOfWork, new Random());
      // but work beyond that must take at least one second
      assertThat(afterBurst).isAtLeast(1000);
    }
  }

  /**

        taskRunner.kickCoordinator(this)
      }
    }
  }

  /**
   * Overload of [schedule] that uses a lambda for a repeating task.
   *
   * TODO: make this inline once this is fixed: https://github.com/oracle/graal/issues/3466
   */
  fun schedule(
    name: String,
    delayNanos: Long = 0L,
    block: () -> Long,
  ) {
    schedule(
      object : Task(name) {

    AtomicInteger totalCalls = new AtomicInteger();
    Runnable intCounter =
        new Runnable() {
          @Override
          public void run() {
            totalCalls.incrementAndGet();
            // Make sure that no other tasks are scheduled to run while this is running.
            assertFalse(fakePool.hasNext());
          }
        };

    assertFalse(fakePool.hasNext());
    e.execute(intCounter);

     * Given that we declare this method as accepting and returning non-nullable values (because we
     * implement Function<A, B>, as discussed in a class-level comment), it would make some sense to
     * perform runtime null checks on the input and output. (That would also make NullPointerTester
     * happy!) However, since we didn't do that for many years, we're not about to start now.

Concurrency
===========

This document describes the concurrency considerations for http/2 connections and the connection pool within OkHttp.

## HTTP/2 Connections

The HttpURLConnection API is a blocking API. You make a blocking write to send a request, and a blocking read to receive the response.

#### Blocking APIs

  /** How many times a new task has been started. Guarded by `this`. */
  private var contextSwitchCount = 0

  /** Guarded by `this`. */
  private var activeThreads = 0

  /** A task runner that posts tasks to this fake. Tasks won't be executed until requested. */
  val taskRunner: TaskRunner =
    TaskRunner(
      object : TaskRunner.Backend {
        override fun execute(
          taskRunner: TaskRunner,
          runnable: Runnable,

  @Override
  public final void run() {
    /*
     * Set runner thread before checking isDone(). If we were to check isDone() first, the task
     * might be cancelled before we set the runner thread. That would make it impossible to
     * interrupt, yet it will still run, since interruptTask will leave the runner value null,
     * allowing the CAS below to succeed.
     */
    Thread currentThread = Thread.currentThread();

        }
      }

    // Make the first request waiting until we get our auth challenge.
    val request = Request(server.url("/"))
    blockingAuthClient.newCall(request).enqueue(callback)
    val response1 = responses.take()
    assertThat(response1).isEqualTo("")
    assertThat(server.takeRequest().exchangeIndex).isEqualTo(0)