}

    fun flowControlListener(flowControlListener: FlowControlListener) =
      apply {
        this.flowControlListener = flowControlListener
      }

    fun build(): Http2Connection = Http2Connection(this)
  }

  /**
   * Methods in this class must not lock FrameWriter. If a method needs to write a frame, create an
   * async task to do so.
   */

  private fun connect(
    peer: MockHttp2Peer,
    pushObserver: PushObserver = IGNORE,
    listener: Http2Connection.Listener = Http2Connection.Listener.REFUSE_INCOMING_STREAMS,
  ): Http2Connection {
    val connection =
      Http2Connection
        .Builder(true, TaskRunner.INSTANCE)
        .socket(peer.openSocket().asBufferedSocket(), "peer")
        .pushObserver(pushObserver)
        .listener(listener)

    val http2Connection =
      Http2Connection
        .Builder(client = true, taskRunner)
        .socket(socket, route.address.url.host)
        .listener(this)
        .pingIntervalMillis(pingIntervalMillis)
        .flowControlListener(flowControlListener)
        .build()
    this.http2Connection = http2Connection

import okhttp3.internal.closeQuietly
import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.connection.asBufferedSocket
import okhttp3.internal.http2.Header
import okhttp3.internal.http2.Http2Connection
import okhttp3.internal.http2.Http2Stream
import okhttp3.internal.platform.Platform
import okhttp3.tls.internal.TlsUtil.localhost
import okio.buffer
import okio.source

/** Encode requests and responses using HTTP/2 frames. */
class Http2ExchangeCodec(
  client: OkHttpClient,
  override val carrier: Carrier,
  private val chain: RealInterceptorChain,
  private val http2Connection: Http2Connection,
) : ExchangeCodec {
  @Volatile private var stream: Http2Stream? = null

  private val protocol: Protocol =
    if (Protocol.H2_PRIOR_KNOWLEDGE in client.protocols) {
      Protocol.H2_PRIOR_KNOWLEDGE

    val connection = routePlanner.plans.first().connection
    val http2Connection = connectHttp2(peer, connection, 5)
    setPolicy(pool, address, AddressPolicy(5))
    assertThat(pool.connectionCount()).isEqualTo(1)

    // Decrease the connection's max so that another connection is needed
    updateMaxConcurrentStreams(http2Connection, 4)
    assertThat(pool.connectionCount()).isEqualTo(2)

              override fun writeTo(sink: BufferedSink) {
                sink.write(postBytes) // push bytes into the stream's buffer
                sink.flush() // Http2Connection.writeData subject to write window
                sink.close() // Http2Connection.writeData empty frame
              }
            },
        ),
      )
    val response = call.execute()
    assertThat(response.body.string()).isEqualTo("ABCDE")

import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.http.HttpMethod
import okhttp3.internal.http2.ErrorCode
import okhttp3.internal.http2.Header
import okhttp3.internal.http2.Http2Connection
import okhttp3.internal.http2.Http2Stream
import okhttp3.internal.immutableListOf
import okhttp3.internal.platform.Platform
import okhttp3.internal.threadFactory
import okhttp3.internal.toImmutableList

import mockwebserver3.junit5.StartStop
import okhttp3.Headers.Companion.headersOf
import okhttp3.HttpUrl.Companion.toHttpUrl
import okhttp3.ResponseBody.Companion.toResponseBody
import okhttp3.internal.http2.Http2Connection.Companion.OKHTTP_CLIENT_WINDOW_SIZE
import okhttp3.testing.PlatformRule
import okio.BufferedSource
import okio.IOException
import okio.Path.Companion.toPath
import okio.fakefilesystem.FakeFileSystem
import okio.use

import okio.Socket
import okio.Source
import okio.Timeout

/** A logical bidirectional stream. */
@Suppress("NAME_SHADOWING")
class Http2Stream internal constructor(
  val id: Int,
  val connection: Http2Connection,
  outFinished: Boolean,
  inFinished: Boolean,
  headers: Headers?,
) : Lockable,
  Socket {
  // Internal state is guarded by `this`. No long-running or potentially blocking operations are