proxy selection process.
 *  New: `Response.byteString()` reads the entire response into memory as a byte string.
 *  New: `OkHttpClient.x509TrustManager` accessor.
 *  New: Permit [new WebSocket response codes][iana_websocket]: 1012 (Service Restart), 1013 (Try
    Again Later), and 1014 (invalid response from the upstream).

   * network interceptors return.
   */
  internal var interceptorScopedExchange: Exchange? = null
    private set

  // These properties are guarded by [lock]. They are typically only accessed by the thread executing
  // the call, but they may be accessed by other threads for duplex requests.

  /** True if this call still has a request body open. */
  private var requestBodyOpen = false

  /** The maximum size of [buffer]. */
  val bufferMaxSize: Long,
) {
  /** The thread that currently has access to upstream. Possibly null. Guarded by this. */
  var upstreamReader: Thread? = null

  /**
   * A buffer for [upstreamReader] to use when pulling bytes from upstream. Only the
   * [upstreamReader] thread may access this buffer.
   */
  val upstreamBuffer = Buffer()

import okhttp3.internal.tls.CertificateChainCleaner
import okhttp3.internal.tls.TrustRootIndex
import okio.Buffer
import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement

/**
 * Access to platform-specific features.
 *
 * ### Session Tickets
 *
 * Supported on Android 2.3+.
 * Supported on JDK 8+ via Conscrypt.
 *
 * ### ALPN (Application Layer Protocol Negotiation)
 *

import okio.BufferedSink
import okio.BufferedSource

/**
 * A connection to a remote web server capable of carrying 1 or more concurrent streams.
 *
 * Connections are shared in a connection pool. Accesses to the connection's state must be guarded
 * by holding a lock on the connection.
 */
class RealConnection(
  val taskRunner: TaskRunner,
  val connectionPool: RealConnectionPool,
  override val route: Route,

    that this class is not strictly immutable as it has stateful members like
    the connection pool and cache.

 *  **Get and Set prefixes are now avoided.** With ubiquitous builders
    throughout OkHttp these accessor prefixes aren't necessary. Previously
    OkHttp used _get_ and _set_ prefixes sporadically which make the API
    inconsistent and awkward to explore.

        .add("content-length", "99")
        .add("authorization", "peanutbutter")
        .add("proxy-authorization", "chocolate")
        .add("cookie", "drink=coffee")
        .add("set-cookie", "accessory=sugar")
        .add("user-agent", "OkHttp")
        .build()
    val request =
      Request(
        "https://square.com".toHttpUrl(),
        headers,
      )

  private var nextTcpConnectAtNanos = Long.MIN_VALUE

  /**
   * Plans currently being connected, and that will later be added to [connectResults]. This is
   * mutated by the call thread only. If is accessed by background connect threads.
   */
  private val tcpConnectsInFlight = CopyOnWriteArrayList<Plan>()

  /**
   * Results are posted here as they occur. The find job is done when either one plan completes

URLs (like `https://github.com/square/okhttp`) are fundamental to HTTP and the Internet. In addition to being a universal, decentralized naming scheme for everything on the web, they also specify how to access web resources.

URLs are abstract:

import okhttp3.tls.HeldCertificate
import okhttp3.tls.internal.TlsUtil.localhost
import okio.Buffer
import org.junit.jupiter.api.AfterEach
import org.junit.jupiter.api.Disabled
import org.junit.jupiter.api.Test

/**
 * Access every declaration that is deprecated with [DeprecationLevel.ERROR]. Although new Kotlin
 * code shouldn't use these, they're necessary for clients migrating from OkHttp 3.x and this test