private boolean isRecoverableError(Exception error) {
        // Timeout errors are often recoverable
        if (error instanceof SocketTimeoutException) {
            return true;
        }

        // Some socket errors might be recoverable
        if (error instanceof SocketException) {
            String message = error.getMessage();
            if (message != null) {
                message = message.toLowerCase();

   */
  fun cancel()

  fun interface Factory {
    /**
     * Creates a new event source and immediately returns it. Creating an event source initiates an
     * asynchronous process to connect the socket. Once that succeeds or fails, `listener` will be
     * notified. The caller must cancel the returned event source when it is no longer in use.
     */
    fun newEventSource(
      request: Request,

    println("Proxy Server 1 is ${server1.socketAddress}")
    println("Proxy Server 2 is ${server2.socketAddress}")

    // Since myproxy:8008 won't resolve, redirect with DNS to proxyServer1
    // Then redirect socket connection to server1
    dns["myproxy"] = listOf(proxyServer1)
    socketFactory[proxyServer1] = server1.socketAddress

    client = client.newBuilder().proxySelector(proxySelector).build()

          object : EventListener() {
            override fun connectionAcquired(
              call: Call,
              connection: Connection,
            ) {
              val sslSocket = connection.socket() as SSLSocket
              println("Requested " + sslSocket.sslParameters.applicationProtocols.joinToString())
              println("Negotiated " + sslSocket.applicationProtocol)
            }
          },

import assertk.assertions.hasSize
import assertk.assertions.isEqualTo
import java.io.IOException
import java.net.Inet4Address
import java.net.Inet6Address
import java.net.InetAddress
import java.net.Socket
import java.util.concurrent.CountDownLatch
import java.util.concurrent.TimeUnit
import javax.net.SocketFactory
import kotlin.test.assertFailsWith
import mockwebserver3.MockResponse
import mockwebserver3.MockWebServer

        .socketFactory(
          object : DelegatingSocketFactory(getDefault()) {
            override fun configureSocket(socket: Socket): Socket {
              socket.receiveBufferSize = socketBufferSize
              socket.sendBufferSize = socketBufferSize
              return socket
            }
          },
        ).writeTimeout(Duration.ofMillis(500))
        .build()
    server.start()

    when explicitly forbidden.
 *  Fix: Throw a `SSLPeerUnverifiedException` when host verification fails.
 *  Fix: MockWebServer explicitly closes sockets. (On some Android releases,
    closing the input stream and output stream of a socket is not sufficient.
 *  Fix: Buffer outgoing HTTP/2 frames to limit how many outgoing frames are
    created.
 *  Fix: Avoid crashing when cache writing fails due to a full disk.

  when {
    // If there was a protocol problem, don't recover.
    e is ProtocolException -> false

    // If there was an interruption or timeout (SocketTimeoutException), don't recover.
    // For the socket connect timeout case we do not try the same host with a different
    // ConnectionSpec: we assume it is unreachable.
    e is InterruptedIOException -> false

    int DEFAULT_PORT = 445;

    /** Default maximum multiplex count */
    int DEFAULT_MAX_MPX_COUNT = 10;
    /** Default response timeout in milliseconds */
    int DEFAULT_RESPONSE_TIMEOUT = 30000;
    /** Default socket timeout in milliseconds */
    int DEFAULT_SO_TIMEOUT = 35000;
    /** Default receive buffer size in bytes */
    int DEFAULT_RCV_BUF_SIZE = 60416;
    /** Default send buffer size in bytes */

 *  New: charset support for `Credentials.basic()`.


## Version 3.5.0

_2016-11-30_

 *  **Web Sockets are now a stable feature of OkHttp.** Since being introduced as a beta feature in
    OkHttp 2.3 our web socket client has matured. Connect to a server's web socket with
    `OkHttpClient.newWebSocket()`, send messages with `send()`, and receive messages with the
    `WebSocketListener`.