// $0.05 worth of phone storage in 2020
          maxSize = 50L * 1024L * 1024L // 50 MiB
      ))
      .build()
```

## EventListener events 

Cache Events are exposed via the EventListener API.  Typical scenarios are below.

### Cache Hit

In the ideal scenario the cache can fulfill the request without any conditional call to the network.

    new PrintEvents().run();
  }

  private static final class PrintingEventListener extends EventListener {
    private static final Factory FACTORY = new Factory() {
      final AtomicLong nextCallId = new AtomicLong(1L);

      @Override public EventListener create(Call call) {
        long callId = nextCallId.getAndIncrement();
        System.out.printf("%04d %s%n", callId, call.request().url());

    val sessionIds = mutableListOf<String>()

    assumeNetwork()

    client =
      client.newBuilder()
        .eventListenerFactory(
          clientTestRule.wrap(
            object : EventListener() {
              override fun connectionAcquired(
                call: Call,
                connection: Connection,
              ) {
                val sslSocket = connection.socket() as SSLSocket

          }
        }
      }

    client =
      client.newBuilder()
        .connectionSpecs(listOf(spec))
        .eventListenerFactory(
          clientTestRule.wrap(
            object : EventListener() {
              override fun connectionAcquired(
                call: Call,
                connection: Connection,
              ) {
                val sslSocket = connection.socket() as SSLSocket

import java.io.IOException
import java.net.InetAddress
import java.net.InetSocketAddress
import java.net.Proxy
import okhttp3.internal.SuppressSignatureCheck

/** Data classes that correspond to each of the methods of [EventListener]. */
@SuppressSignatureCheck
sealed class CallEvent {
  abstract val timestampNs: Long
  abstract val call: Call

  val name: String
    get() = javaClass.simpleName

 * [RFC 2817][1]. The HTTP CONNECT request that creates this tunnel connection is special: it
 * does not participate in any [interceptors][Interceptor] or [event listeners][EventListener]. It
 * doesn't include the motivating request's HTTP headers or even its full URL; only the target
 * server's hostname is sent to the proxy.
 *

import org.junit.jupiter.api.Assertions.fail

open class RecordingEventListener(
  /**
   * An override to ignore the normal order that is enforced.
   * EventListeners added by Interceptors will not see all events.
   */
  private val enforceOrder: Boolean = true,
) : EventListener() {
  val eventSequence: Deque<CallEvent> = ConcurrentLinkedDeque()

  private val forbiddenLocks = mutableListOf<Any>()

import okio.IOException
import org.junit.jupiter.api.Assertions

open class RecordingConnectionListener(
  /**
   * An override to ignore the normal order that is enforced.
   * EventListeners added by Interceptors will not see all events.
   */
  private val enforceOrder: Boolean = true,
) : ConnectionListener() {
  val eventSequence: Deque<ConnectionEvent> = ConcurrentLinkedDeque()