* used so that OkHttp can learn from its mistakes: if there was a failure attempting to connect to
 * a specific IP address or proxy server, that failure is remembered and alternate routes are
 * preferred.
 */
class RouteDatabase {
  private val _failedRoutes = mutableSetOf<Route>()

  val failedRoutes: Set<Route>
    @Synchronized get() = _failedRoutes.toSet()

  /** Records a failure connecting to [failedRoute]. */

 * IP address, and TLS mode. Connections may also be recycled.
 */
class RouteSelector internal constructor(
  private val address: Address,
  private val routeDatabase: RouteDatabase,
  private val call: RealCall,
  private val fastFallback: Boolean,
) {
  // State for negotiating the next proxy to use.
  private var proxies = emptyList<Proxy>()
  private var nextProxyIndex: Int = 0

      pingIntervalMillis = client.pingIntervalMillis,
      retryOnConnectionFailure = client.retryOnConnectionFailure,
      fastFallback = client.fastFallback,
      address = address,
      routeDatabase = client.routeDatabase,
      call = call,
      request = call.request(),
    )
  }

  override fun close() {
    taskFaker.close()
  }