*/
  @Throws(UnknownHostException::class)
  fun lookup(hostname: String): List<InetAddress>

  companion object {
    /**
     * A DNS that uses [InetAddress.getAllByName] to ask the underlying operating system to
     * lookup IP addresses. Most custom [Dns] implementations should delegate to this instance.
     */
    @JvmField
    val SYSTEM: Dns = DnsSystem()

    private class DnsSystem : Dns {

  val referer: String? by option("-e", "--referer", help = "Referer URL")

  val verbose: Boolean by option("-v", "--verbose", help = "Makes $NAME verbose during the operation").flag()

  val sslDebug: Boolean by option(help = "Output SSL Debug").flag()

  val url: String? by argument(name = "url", help = "Remote resource URL")

  var client: Call.Factory? = null

        return new MetricsEventListener(call);
      } else {
        return EventListener.NONE;
      }
    }
  };

  ...
}
```

### Events with Failures

   * doesn't include framing overhead. If compression is enabled, uncompressed messages size
   * is used to calculate this value. It also doesn't include any bytes buffered by the operating
   * system or network intermediaries. This method returns 0 if no messages are waiting in the
   * queue. If may return a nonzero value after the web socket has been canceled; this indicates

 * [okhttp-stats](https://github.com/flipkart-incubator/okhttp-stats): Get stats like average network speed.
 * [okhttp-system-keystore](https://github.com/charleskorn/okhttp-system-keystore): Use trusted certificates from the operating system keystore (Keychain on macOS, Certificate Store on Windows).
 * ⬜️ [Okio](https://github.com/square/okio/): A modern I/O API for Java.

   * canceled. For example, happy-path events like [requestHeadersStart] and [requestHeadersEnd] may
   * occur after a call is canceled. Typically cancellation takes effect when an expensive I/O
   * operation is required.
   *
   * This is invoked at most once, even if [Call.cancel] is invoked multiple times. It may be
   * invoked at any point in a call's life, including before [callStart] and after [callEnd].
   */

   *
   *   o READ lines track accesses for LRU.
   *
   *   o REMOVE lines track entries that have been deleted.
   *
   * The journal file is appended to as cache operations occur. The journal may occasionally be
   * compacted by dropping redundant lines. A temporary file named "journal.tmp" will be used during
   * compaction; that file should be deleted if it exists when the cache is opened.

      exactRuleLabels
    } else {
      wildcardRuleLabels
    }
  }

  /**
   * Reads the public suffix list treating the operation as uninterruptible. We always want to read
   * the list otherwise we'll be left in a bad state. If the thread was interrupted prior to this
   * operation, it will be re-interrupted after the list is read.
   */
  private fun readTheListUninterruptibly() {
    var interrupted = false
    try {

#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
#       see the in-line comments for details.
#
#       There are tweaks for specific operating systems such as AIX, CygWin,
#       Darwin, MinGW, and NonStop.
#
#   (3) This script is generated from the Groovy template

  headers: Headers?,
) {
  internal val lock: ReentrantLock = ReentrantLock()
  val condition: Condition = lock.newCondition()

  // Internal state is guarded by [lock]. No long-running or potentially blocking operations are
  // performed while the lock is held.

  /** The bytes consumed and acknowledged by the stream. */
  val readBytes: WindowCounter = WindowCounter(id)

  /** The total number of bytes produced by the application. */