* connection the client has many options:
 *
 *  * **HTTP proxy:** a proxy server may be explicitly configured for the client. Otherwise, the
 *    [proxy selector][java.net.ProxySelector] is used. It may return multiple proxies to attempt.
 *  * **IP address:** whether connecting directly to an origin server or a proxy, opening a socket

    return delegate!!.handshakeApplicationProtocol
  }

  override fun setHandshakeApplicationProtocolSelector(selector: BiFunction<SSLSocket, MutableList<String>, String>?) {
    delegate!!.handshakeApplicationProtocolSelector = selector
  }

  override fun getHandshakeApplicationProtocolSelector(): BiFunction<SSLSocket, MutableList<String>, String> {

    // If we have a routes left, use 'em.
    if (routeSelection?.hasNext() == true) return true

    // If we haven't initialized the route selector yet, assume it'll have at least one route.
    val localRouteSelector = routeSelector ?: return true

    // If we do have a route selector, use its routes.
    return localRouteSelector.hasNext()
  }

  /**

    if (!isRecoverable(e, requestSendStarted)) return false

    // No more routes to attempt.
    if (!call.retryAfterFailure()) return false

    // For failure recovery, use the same route selector with a new connection.
    return true
  }

  private fun requestIsOneShot(
    e: IOException,
    userRequest: Request,
  ): Boolean {
    val requestBody = userRequest.body

  @ArgumentsSource(FileSystemParamProvider::class)
  fun recoverFromInitializationFailure(parameters: Pair<FileSystem, Boolean>) {
    setUp(parameters.first, parameters.second)
    // Add an uncommitted entry. This will get detected on initialization, and the cache will
    // attempt to delete the file. Do not explicitly close the cache here so the entry is left as
    // incomplete.
    val creator = cache.edit("k1")!!

  private var server: MockWebServer? = null

  @BeforeEach fun setUp(server: MockWebServer?) {
    this.server = server
  }

  @AfterEach fun tearDown() {
    ProxySelector.setDefault(DEFAULT_PROXY_SELECTOR)
    CookieManager.setDefault(DEFAULT_COOKIE_HANDLER)
    ResponseCache.setDefault(DEFAULT_RESPONSE_CACHE)
  }

  @Test fun durationDefaults() {
    val client = clientTestRule.newClient()

   * Returns this address's explicitly-specified HTTP proxy, or null to delegate to the
   * [proxy selector][proxySelector].
   */
  @get:JvmName("proxy") val proxy: Proxy?,
  protocols: List<Protocol>,
  connectionSpecs: List<ConnectionSpec>,
  /**
   * Returns this address's proxy selector. Only used if the proxy is null. If none of this
   * selector's proxies are reachable, a direct connection will be attempted.
   */

   * only [Proxy.NO_PROXY]. This comes up in several situations:
   *
   * * If neither a proxy nor proxy selector is configured.
   * * If the proxy is configured explicitly as [Proxy.NO_PROXY].
   * * If the proxy selector returns only [Proxy.NO_PROXY].
   * * If the proxy selector returns an empty list or null.
   *
   * Otherwise it lists the proxies in the order they will be attempted.
   *

   *     CLEAN or REMOVE indicate that temporary files may need to be deleted.
   *
   *   o CLEAN lines track a cache entry that has been successfully published and may be read. A
   *     publish line is followed by the lengths of each of its values.
   *
   *   o READ lines track accesses for LRU.
   *
   *   o REMOVE lines track entries that have been deleted.
   *

 * A or AAAA records, and returns the addresses or exception.
 *
 * Two instances must be used to get all results for an address.
 *
 * @param network network to use, if not selects the default network.
 */
@RequiresApi(Build.VERSION_CODES.Q)
@ExperimentalOkHttpApi
class AndroidAsyncDns(
  private val dnsClass: AsyncDns.DnsClass,
  private val network: Network? = null,
) : AsyncDns {