private val connectionUser: ConnectionUser,
  private val fastFallback: Boolean,
) {
  // State for negotiating the next proxy to use.
  private var proxies = emptyList<Proxy>()
  private var nextProxyIndex: Int = 0

  // State for negotiating the next socket address to use.
  private var inetSocketAddresses = emptyList<InetSocketAddress>()

  // State for negotiating failed routes
  private val postponedRoutes = mutableListOf<Route>()

            // from being reused. Otherwise we're still obligated to transmit the request body to
            // leave the connection in a consistent state.
            exchange.noNewExchangesOnConnection()
          }
        }
      } else {
        exchange.noRequestBody()
      }

      if (requestBody == null || !requestBody.isDuplex()) {

  }

  @Test fun setDate() {
    val expected = Date(1000)
    val headers =
      Headers.Builder()
        .add("testDate", Date(0L))
        .set("testDate", expected)
        .build()
    assertThat(headers["testDate"]).isEqualTo("Thu, 01 Jan 1970 00:00:01 GMT")
    assertThat(headers.getDate("testDate")).isEqualTo(expected)
  }

  @Test fun setInstant() {

      Thread currentThread = Thread.currentThread();
      String originalName = currentThread.getName();
      currentThread.setName("Crawler " + url);
      try {
        fetch(url);
      } catch (IOException e) {
        System.out.printf("XXX: %s %s%n", url, e);
      } finally {
        currentThread.setName(originalName);
      }
    }
  }

  public void fetch(HttpUrl url) throws IOException {

              return socket
            }
          },
        )
        .build()
  }

  @AfterEach
  fun tearDown() {
    Thread.interrupted() // Clear interrupted state.
  }

  @Test
  fun interruptWritingRequestBody() {
    server.enqueue(MockResponse())
    server.start()
    val call =
      client.newCall(
        Request.Builder()
          .url(server.url("/"))

 *
 *  * **Canceled:** the web socket connection failed. Messages that were successfully enqueued by
 *    either peer may not have been transmitted to the other.
 *
 * Note that the state progression is independent for each peer. Arriving at a gracefully-closed
 * state indicates that a peer has sent all of its outgoing messages and received all of its
 * incoming messages. But it does not guarantee that the other peer will successfully receive all of