connection.calls.add(CallReference(this, callStackTrace))
  }

  /**
   * Releases resources held with the request or response of [exchange]. This should be called when
   * the request completes normally or when it fails due to an exception, in which case [e] should
   * be non-null.
   *
   * If the exchange was canceled or timed out, this will wrap [e] in an exception that provides

  /**
   * If true, no new exchanges can be created on this connection. It is necessary to set this to
   * true when removing a connection from the pool; otherwise a racing caller might get it from the
   * pool when it shouldn't. Symmetrically, this must always be checked before returning a
   * connection from the pool.
   *
   * Once true this is always true. Guarded by this.
   */
  var noNewExchanges = false

  /**

## Version 4.5.0

_2020-04-06_

**This release fixes a severe bug where OkHttp incorrectly detected and recovered from unhealthy
connections.** Stale or canceled connections were incorrectly attempted when they shouldn't have
been, leading to rare cases of infinite retries. Please upgrade to this release!

 *  Fix: don't return stale DNS entries in `DnsOverHttps`. We were caching DNS results indefinitely

    }.also { expected ->
      assertThat(expected.message).isEqualTo("timeout")
    }
  }

  /**
   * We delay sending the last byte of the request body 1500 ms. The 1000 ms read timeout shouldn't
   * elapse because it shouldn't start until the request body is sent.
   */
  @Test
  fun headersReadTimeoutDoesNotStartUntilLastRequestBodyByteNoFire() {
    enableProtocol(Protocol.HTTP_2)
    server.enqueue(

    assertThat(url.queryParameter("a")).isEqualTo("!$(),/:;?@[]\\^`{|}~")
  }

  /**
   * When callers parse a URL with query components that aren't encoded, we shouldn't convert them
   * into a canonical form because doing so could be semantically different.
   */
  @Test
  fun queryCharactersNotReencodedWhenParsed() {
    val url = parse("http://host/?a=!$(),/:;?@[]\\^`{|}~")

    call.cancel()
    assertFailsWith<IOException> {
      // Reading 'B' may succeed if it's buffered.
      inputStream.read()

      // But 'C' shouldn't be buffered (the response is throttled) and this should fail.
      inputStream.read()
    }
    inputStream.close()
  }

  @Test
  fun disconnectDuringConnect_cookieJar() {
    val callReference = AtomicReference<Call>()

 *
 * Implementations should check if the initial request already included an attempt to
 * authenticate. If so it is likely that further attempts will not be useful and the authenticator
 * should give up.
 *
 * When reactive authentication is requested by an origin web server, the response code is 401
 * and the implementation should respond with a new request that sets the "Authorization" header.
 *

    address: Address,
    policy: AddressPolicy,
  ) {
    delegate.setPolicy(address, policy)
  }

  /**
   * A policy for how the pool should treat a specific address.
   */
  class AddressPolicy(
    /**
     * How many concurrent calls should be possible to make at any time.
     * The pool will routinely try to pre-emptively open connections to satisfy this minimum.

/**
 * Tests for round-tripping headers through hpack.
 *
 * TODO: update hpack-test-case with the output of our encoder.
 * This test will hide complementary bugs in the encoder and decoder,
 * We should test that the encoder is producing responses that are
 */
class HpackRoundTripTest : HpackDecodeTestBase() {
  internal class StoriesTestProvider : SimpleProvider() {

   * headers.
   *
   * Official OkHttp releases follow [semantic versioning][semver]. Versions with the `-SNAPSHOT`
   * qualifier are not unique and should only be used in development environments. If you create
   * custom builds of OkHttp please include a qualifier your version name, like "4.7.0-mycompany.3".
   * The version string is configured in the root project's `build.gradle`.