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)

  /** 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,

        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) {

 * **reactive** authentication after receiving a challenge from either an origin web server or proxy
 * server.
 *
 * ## Preemptive Authentication
 *
 * To make HTTPS calls using an HTTP proxy server OkHttp must first negotiate a connection with
 * the proxy. This proxy connection is called a "TLS Tunnel" and is specified by

            classes that are actually used in the module under test.

            One way to eliminate the warnings is to make base.testModule include the not really
            necessary <inherits> lines for c.g.c.collect.testModule, etc. However, adding <inherits>
            lines could make c.g.c.base.testModule transitively inherit from extra modules. If some

     * 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

  /**
   * Creates an ImmutableMap from the first n entries in entryArray. This implementation may replace
   * the entries in entryArray with its own entry objects (though they will have the same key/value
   * contents), and may take ownership of entryArray.
   */
  static <K, V> ImmutableMap<K, V> fromEntryArray(
      int n, @Nullable Entry<K, V>[] entryArray, boolean throwIfDuplicateKeys) {
    checkPositionIndex(n, entryArray.length);
    if (n == 0) {

import java.util.Iterator;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;

/**
 * Handler for dispatching events to subscribers, providing different event ordering guarantees that
 * make sense for different situations.
 *
 * <p><b>Note:</b> The dispatcher is orthogonal to the subscriber's {@code Executor}. The dispatcher

        }
      }

    // 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)