TYPE_DATA -> readData(handler, length, flags, streamId)
      TYPE_HEADERS -> readHeaders(handler, length, flags, streamId)
      TYPE_PRIORITY -> readPriority(handler, length, flags, streamId)
      TYPE_RST_STREAM -> readRstStream(handler, length, flags, streamId)
      TYPE_SETTINGS -> readSettings(handler, length, flags, streamId)
      TYPE_PUSH_PROMISE -> readPushPromise(handler, length, flags, streamId)

  ) {
    this.withLock {
      if (closed) throw IOException("closed")
      var flags = FLAG_NONE
      if (outFinished) flags = flags or FLAG_END_STREAM
      dataFrame(streamId, flags, source, byteCount)
    }
  }

  @Throws(IOException::class)
  fun dataFrame(
    streamId: Int,
    flags: Int,
    buffer: Buffer?,
    byteCount: Int,
  ) {
    frameHeader(

 * Settings describe characteristics of the sending peer, which are used by the receiving peer.
 * Settings are [connection][Http2Connection] scoped.
 */
class Settings {
  /** Bitfield of which flags that values. */
  private var set: Int = 0

  /** Flag values. */
  private val values = IntArray(COUNT)

  /** Returns -1 if unset. */
  val headerTableSize: Int
    get() {
      val bit = 1 shl HEADER_TABLE_SIZE

    FLAGS[FLAG_PADDED] = "PADDED"
    for (prefixFlag in prefixFlags) {
      FLAGS[prefixFlag or FLAG_PADDED] = FLAGS[prefixFlag] + "|PADDED"
    }

    FLAGS[FLAG_END_HEADERS] = "END_HEADERS" // Same as END_PUSH_PROMISE.
    FLAGS[FLAG_PRIORITY] = "PRIORITY" // Same as FLAG_COMPRESSED.
    FLAGS[FLAG_END_HEADERS or FLAG_PRIORITY] = "END_HEADERS|PRIORITY" // Only valid on HEADERS.

  }

  data class Request(
    val network: Network?,
    val domain: String,
    val nsType: Int,
    val flags: Int,
    val callback: DnsResolver.Callback<List<InetAddress>>,
  )

  @Implementation
  fun query(
    network: Network?,
    domain: String,
    nsType: Int,
    flags: Int,
    executor: Executor,
    cancellationSignal: CancellationSignal?,
    callback: DnsResolver.Callback<List<InetAddress>>,

    val result = mutableListOf<InetAddress>()

    val buf = Buffer()
    buf.write(byteString)
    buf.readShort() // query id

    val flags = buf.readShort().toInt() and 0xffff
    require(flags shr 15 != 0) { "not a response" }

    val responseCode = flags and 0xf

    if (responseCode == NXDOMAIN) {
      throw UnknownHostException("$hostname: NXDOMAIN")
    } else if (responseCode == SERVFAIL) {

lifetime based on Response cache headers.

 - CallStart 
 - **CacheMiss**
 - ProxySelectStart
 - ... Standard Events ...
 - CallEnd
        
### Conditional Cache Hit
 
When cache flags require checking the cache results are still valid an early cacheConditionalHit event is
received followed by a cache hit or miss.  Critically in the cache hit scenario the server won’t send the response body.

  val allowInsecure: Boolean by option("-k", "--insecure", help = "Allow connections to SSL sites without certs").flag()

  val showHeaders: Boolean by option("-i", "--include", help = "Include protocol headers in the output").flag()

  val showHttp2Frames: Boolean by option("--frames", help = "Log HTTP/2 frames to STDERR").flag()

 *  Fix: Honor `RequestBody.isOneShot()` in `HttpLoggingInterceptor`.


## Version 4.2.2

_2019-10-06_

 *  Fix: When closing a canceled HTTP/2 stream, don't send the `END_STREAM` flag. This could cause
    the server to incorrectly interpret the stream as having completed normally. This is most useful
    when a request body needs to cancel its own call.


## Version 4.2.1

_2019-10-02_

    data.write("ca00".decodeHex()) // Empty pong, flag 1 set.
    assertFailsWith<ProtocolException> {
      clientReader.processNextFrame()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Unexpected rsv1 flag")
    }
  }

  @Test fun reservedFlag1IsUnsupportedForControlFrames() {
    data.write("ca00".decodeHex()) // Empty pong, flag 1 set.
    assertFailsWith<ProtocolException> {