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() {

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

    for (i in FLAGS.indices) { // Fill in holes with binary representation.
      if (FLAGS[i] == null) FLAGS[i] = BINARY[i]
    }
  }

  /**

  }

  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.