Once the response has been received, the connection will be returned to the pool so it can be reused for a future request. Connections are evicted from the pool after a period of inactivity.

### [Fast Fallback](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-ok-http-client/-builder/fast-fallback/)

     * the held certificate, further certificates are included in the handshake so the peer can
     * build a trusted path to a trusted root certificate.
     *
     * The chain should include all intermediate certificates but does not need the root certificate
     * that we expect to be known by the remote peer. The peer already has that certificate so
     * transmitting it is unnecessary.
     */
    fun heldCertificate(

import java.util.logging.Formatter
import java.util.logging.LogRecord

/**
 * Is Java8 Data and Time really this bad, or is writing this on a plane from just javadocs a bad
 * idea?
 *
 * Why so much construction?
 */
class OneLineLogFormat : Formatter() {
  private val d =
    DateTimeFormatterBuilder()
      .appendValue(HOUR_OF_DAY, 2)
      .appendLiteral(':')
      .appendValue(MINUTE_OF_HOUR, 2)

import okhttp3.internal.readFieldOrNull

/**
 * Base Android reflection based SocketAdapter for the built in Android SSLSocket.
 *
 * It's assumed to always be present with known class names on Android devices, so we build
 * optimistically via [buildIfSupported].  But it also doesn't assume a compile time API.
 */
class StandardAndroidSocketAdapter(
  sslSocketClass: Class<in SSLSocket>,

  tasks.withType<Test>().configureEach {
    environment("OKHTTP_ROOT", rootDir)
  }

  if (platform == "jdk8alpn") {
    // Add alpn-boot on Java 8 so we can use HTTP/2 without a stable API.
    val alpnBootVersion = alpnBootVersion()
    if (alpnBootVersion != null) {
      val alpnBootJar = configurations.detachedConfiguration(

    server.enqueue(MockResponse().setSocketPolicy(SocketPolicy.DISCONNECT_DURING_REQUEST_BODY))
    // Limit the size of the request body that the server holds in memory to an arbitrary
    // 3.5 MBytes so this test can pass on devices with little memory.
    server.bodyLimit = 7 * 512 * 1024
    val connection = server.url("/").toUrl().openConnection() as HttpURLConnection
    connection.setRequestMethod("POST")

   */
  @Test fun proxySelectorNotCalledForNullHost() {
    // The string '>' is okay in a hostname in HttpUrl, which does very light hostname validation.
    // It is not okay in URI, and so it's stripped and we get a URI with a null host.
    val bogusHostname = ">"
    val address =
      factory.newAddress(
        uriHost = bogusHostname,
        uriPort = uriPort,
      )

   * the internal list.
   */
  @JvmStatic
  fun fragmentBuffer(buffer: Buffer): Buffer {
    // Write each byte into a new buffer, then clone it so that the segments are shared.
    // Shared segments cannot be compacted so we'll get a long chain of short segments.
    val result = Buffer()
    while (!buffer.exhausted()) {
      val box = Buffer()
      box.write(buffer, 1)
      result.write(box.copy(), 1)

          registerTest(access, testClass)
        }
      } catch (e: Exception) {
        // If you throw an exception here then native image building fails half way through
        // silently without rewriting the binary. So we report noisily, but keep going and prefer
        // running most tests still.
        e.printStackTrace()
      }
    }
  }

  private fun registerTest(
    access: Feature.BeforeAnalysisAccess,

        TestUtil.UNREACHABLE_ADDRESS_IPV4.address,
      )
    serverIpv4.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE)
    serverIpv6.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE)

    // Yield the first IP address so the second IP address completes first.
    val firstConnectLatch = CountDownLatch(1)
    val socketFactory =
      object : DelegatingSocketFactory(SocketFactory.getDefault()) {
        var first = true