* response body is [closed][ResponseBody]. The recipient of the callback may consume the response
   * body on another thread.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   */
  @Throws(IOException::class)
  fun onResponse(
    call: Call,

A single HTTP call may require follow-up requests to be made to handle authentication challenges, redirects, and HTTP-layer timeouts. In such cases multiple connections, requests, and responses may be attempted. Follow-ups are another reason a single call may trigger multiple events of the same type.

### Threads

#### Application's calling thread

The application-layer must block on writing I/O. We can't return from a write until we've pushed its bytes onto the socket. Otherwise, if the write fails we are unable to deliver its IOException to the application. We would have told the application layer that the write succeeded, but it didn't!

 * limitations under the License.
 */
package okhttp3

import java.io.IOException
import java.util.concurrent.TimeUnit

/**
 * Records received HTTP responses so they can be later retrieved by tests.
 */
class RecordingCallback : Callback {
  private val responses = mutableListOf<RecordedResponse>()

  @Synchronized
  override fun onFailure(
    call: Call,
    e: IOException,
  ) {

) : ExchangeFinder {
  private val connectDelayNanos = TimeUnit.MILLISECONDS.toNanos(250L)
  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>()

  /**

      if (task.nextExecuteNanoTime <= executeNanoTime) {
        taskRunner.logger.taskLog(task, this) { "already scheduled" }
        return false
      }
      futureTasks.removeAt(existingIndex) // Already scheduled later: reschedule below!
    }
    task.nextExecuteNanoTime = executeNanoTime
    taskRunner.logger.taskLog(task, this) {
      if (recurrence) {
        "run again after ${formatDuration(executeNanoTime - now)}"

   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *

# Module okhttp-tls

          invokeStartEvent = false
        }
        if (responseBuilder == null) {
          if (requestBody.isDuplex()) {
            // Prepare a duplex body so that the application can send a request body later.
            exchange.flushRequest()
            val bufferedRequestBody = exchange.createRequestBody(request, true).buffer()
            requestBody.writeTo(bufferedRequestBody)
          } else {

   developers and others in the free software community to coordinate our efforts.

 * **Be pragmatic**: Questions are encouraged and should be asked early in the process to avoid
   problems later. Be thoughtful and considerate when seeking out the appropriate forum for your
   questions. Those who are asked should be responsive and helpful.