this because it only occurs if you have proxy configured and you share a connection pool among
    multiple `OkHttpClient` instances.

    This particularly-subtle bug was caused by us assigning each `OkHttpClient` instance its own
    `NullProxySelector` when an explicit proxy is configured. But we don't share connections when
    the proxy selectors are different. Ugh!


## Version 4.2.0

   *
   * Once true this is always true. Guarded by this.
   */
  var noNewExchanges = false

  /**
   * If true, this connection may not be used for coalesced requests. These are requests that could
   * share the same connection without sharing the same hostname.
   */
  private var noCoalescedConnections = false

  /**
   * The number of times there was a problem establishing a stream that could be due to route

    @JvmField val PREFIX_DIRTY = "OkHttp DIRTY :(\n".encodeUtf8()
    private const val FILE_HEADER_SIZE = 32L

    /**
     * Creates a new relay that reads a live stream from [upstream], using [file] to share that data
     * with other sources.
     *
     * **Warning:** callers to this method must immediately call [newSource] to create a source and
     * close that when they're done. Otherwise a handle to [file] will be leaked.

 *
 * The task runner is also responsible for releasing held threads when the library is unloaded.
 * This is for the benefit of container environments that implement code unloading.
 *
 * Most applications should share a process-wide [TaskRunner] and use queues for per-client work.
 */
class TaskRunner(
  val backend: Backend,
  internal val logger: Logger = TaskRunner.logger,
) {
  val lock: ReentrantLock = ReentrantLock()

        }
      }
    }
  }

  /**
   * Object class to adapter type. This approach limits us to one adapter per Kotlin class, which
   * might be too few for values like UTF_STRING and OBJECT_IDENTIFIER that share a Kotlin class but
   * have very different ASN.1 interpretations.
   */
  private val defaultAnyChoices =
    listOf(
      Boolean::class to BOOLEAN,
      BigInteger::class to INTEGER_AS_BIG_INTEGER,

    assertThat(request.tag(String::class.java)).isSameAs(stringTag)
    assertThat(request.tag(Long::class.javaObjectType)).isSameAs(longTag)
  }

  /** Confirm that we don't accidentally share the backing map between objects. */
  @Test
  fun tagsAreImmutable() {
    val builder =
      Request.Builder()
        .url("https://square.com")
    val requestA = builder.tag(String::class.java, "a").build()

   */
  @get:JvmName("hostOnly") val hostOnly: Boolean,
  /**
   * Returns a string describing whether this cookie is sent for cross-site calls.
   *
   * Two URLs are on the same site if they share a [top private domain][HttpUrl.topPrivateDomain].
   * Otherwise, they are cross-site URLs.
   *
   * When a URL is requested, it may be in the context of another URL.
   *

    assertThat(a.dispatcher).isNotNull()
    assertThat(a.connectionPool).isNotNull()
    assertThat(a.sslSocketFactory).isNotNull()
    assertThat(a.x509TrustManager).isNotNull()

    // Multiple clients share the instances.
    val b = client.newBuilder().build()
    assertThat(b.dispatcher).isSameAs(a.dispatcher)
    assertThat(b.connectionPool).isSameAs(a.connectionPool)

OkHttpClient client = new OkHttpClient.Builder()
    .connectionSpecs(Collections.singletonList(spec))
    .build();
```

### Debugging TLS Handshake Failures

The TLS handshake requires clients and servers to share a common TLS version and cipher suite. This
depends on the JVM or Android version, OkHttp version, and web server configuration. If there is no
common cipher suite and TLS version, your call will fail like this:

```

        .signedBy(pinnedRoot)
        .build()
    val attackerSwitch =
      HeldCertificate.Builder()
        .serialNumber(5L)
        .keyPair(attackerIntermediate.keyPair) // share keys between compromised CA and leaf!
        .commonName("attacker")
        .addSubjectAlternativeName("attacker.com")
        .signedBy(pinnedIntermediate)
        .build()
    val phonyVictim =