// We might no longer need some connections
        connectionPool.scheduleCloser()
      }
    }
  }

  override fun handshake(): Handshake? = handshake

  /** Track a bad route in the route database. Other routes will be attempted first. */
  internal fun connectFailed(
    client: OkHttpClient,
    failedRoute: Route,
    failure: IOException,
  ) {

    automatically retry on an unshared connection.
 *  Fix: Don't crash if a TLS tunnel's response body is truncated.
 *  Fix: Don't track unusable routes beyond their usefulness. We had a bug where we could track
    certain bad routes indefinitely; now we only track the ones that could be necessary.
 *  Fix: Defer proxy selection until a proxy is required. This saves calls to `ProxySelector` on

  /**
   * Returns the number of bytes required to encode these headers using HTTP/1.1. This is also the
   * approximate size of HTTP/2 headers before they are compressed with HPACK. This value is
   * intended to be used as a metric: smaller headers are more efficient to encode and transmit.
   */
  fun byteCount(): Long {

import org.junit.jupiter.api.Test

class HpackTest {
  private val bytesIn = Buffer()
  private var hpackReader: Hpack.Reader? = null
  private val bytesOut = Buffer()
  private var hpackWriter: Hpack.Writer? = null

  @BeforeEach
  fun reset() {
    hpackReader = newReader(bytesIn)
    hpackWriter = Hpack.Writer(4096, false, bytesOut)
  }

  /**

  internal val lock: ReentrantLock = ReentrantLock()

  private val hpackBuffer: Buffer = Buffer()
  private var maxFrameSize: Int = INITIAL_MAX_FRAME_SIZE
  private var closed: Boolean = false
  val hpackWriter: Hpack.Writer = Hpack.Writer(out = hpackBuffer)

  @Throws(IOException::class)
  fun connectionPreface() {
    this.withLock {
      if (closed) throw IOException("closed")

  private val source: BufferedSource,
  private val client: Boolean,
) : Closeable {
  private val continuation: ContinuationSource = ContinuationSource(this.source)
  private val hpackReader: Hpack.Reader =
    Hpack.Reader(
      source = continuation,
      headerTableSizeSetting = 4096,
    )

  @Throws(IOException::class)
  fun readConnectionPreface(handler: Handler) {
    if (client) {

    val name = lock.withLock { nextQueueName++ }
    return TaskQueue(this, "Q$name")
  }

  /**
   * Returns a snapshot of queues that currently have tasks scheduled. The task runner does not
   * necessarily track queues that have no tasks scheduled.
   */
  fun activeQueues(): List<TaskQueue> {
    lock.withLock {
      return busyQueues + readyQueues
    }
  }

  fun cancelAll() {
    lock.assertHeld()

 *  New: APIs to iterate and selectively clear the response cache.
 *  New: Support for SOCKS proxies.
 *  New: Support for `TLS_FALLBACK_SCSV`.
 *  New: Update HTTP/2 support to `h2-16` and `hpack-10`.
 *  New: APIs to prevent retrying non-idempotent requests.
 *  Fix: Drop NPN support. Going forward we support ALPN only.
 *  Fix: The hostname verifier is now strict. This is consistent with the hostname

    different from the version that the module was compiled with. Do not use them in published
    libraries. Do not use them if you aren't willing to track changes to them.

 *  Breaking: Drop support for Kotlin Multiplatform.

    We planned to support multiplatform in OkHttp 5.0, but after building it, we weren't happy with

versions and cipher suites in each spec can change with each release. For example, in OkHttp 2.2 we dropped support for SSL 3.0 in response to the [POODLE](https://googleonlinesecurity.blogspot.ca/2014/10/this-poodle-bites-exploiting-ssl-30.html) attack. And in OkHttp 2.3 we dropped support for [RC4](https://en.wikipedia.org/wiki/RC4#Security). As with your desktop web browser, staying up-to-date with OkHttp is the best way to stay secure.

You can build your own connection spec with a custom...