val clientCertificates =
        HandshakeCertificates.Builder()
          .addPlatformTrustedCertificates()
          .addInsecureHost(server.hostName)
          .build()

      // Need fresh client to reset sslSocketFactoryOrNull
      client =
        OkHttpClient.Builder()
          .eventListenerFactory(
            clientTestRule.wrap(
              object : EventListener() {

Some requests will have a cached response. When this cached response isn’t fresh, OkHttp can do a _conditional GET_ to download an updated response if it’s newer than what’s cached. This requires headers like `If-Modified-Since` and `If-None-Match` to be added.

## Rewriting Responses

      this.maxStaleSeconds = maxStaleSecondsLong.commonClampToInt()
    }

    /**
     * Sets the minimum number of seconds that a response will continue to be fresh for. If the
     * response will be stale when [minFresh] have elapsed, the cached response will not be used and
     * a network request will be made.
     *

    // Stalling the socket will cause TWO requests to time out!
    server.enqueue(MockResponse(socketPolicy = StallSocketAtStart))

    // The 3rd request should be sent to a fresh connection.
    server.enqueue(
      MockResponse(body = "fresh connection"),
    )

    // The first call times out.
    val call1 = client.newCall(Request(server.url("/")))
    assertFailsWith<IOException> {
      call1.execute()

     * @param host an IP address or hostname.
     * @param port the IP port associated with the service.
     * @param maxAge time in seconds that this alternative is considered fresh.
     */
    fun alternateService(
      streamId: Int,
      origin: String,
      protocol: ByteString,
      host: String,
      port: Int,
      maxAge: Long,
    )
  }

import okhttp3.Protocol;
import okhttp3.Request;
import okhttp3.Response;

/**
 * This prints events for a single in-flight call. It won't work for multiple concurrent calls
 * because we don't know what callStartNanos refers to.
 */
public final class PrintEventsNonConcurrent {
  private final OkHttpClient client = new OkHttpClient.Builder()
      .eventListener(new PrintingEventListener())
      .build();

          .headers(conditionalRequestHeaders.build())
          .build()
      return CacheStrategy(conditionalRequest, cacheResponse)
    }

    /**
     * Returns the number of milliseconds that the response was fresh for, starting from the served
     * date.
     */
    private fun computeFreshnessLifetime(): Long {
      val responseCaching = cacheResponse!!.cacheControl
      if (responseCaching.maxAgeSeconds != -1) {

        .build(),
    )
    assertThat(get(server.url("/")).body.string()).isEqualTo("A")
    val request =
      Request.Builder()
        .url(server.url("/"))
        .header("Cache-Control", "min-fresh=120")
        .build()
    val response = client.newCall(request).execute()
    assertThat(response.body.string()).isEqualTo("B")
  }

  @Test
  fun requestMaxStale() {
    server.enqueue(

      Header("location", ""),
      Header("max-forwards", ""),
      Header("proxy-authenticate", ""),
      Header("proxy-authorization", ""),
      Header("range", ""),
      Header("referer", ""),
      Header("refresh", ""),
      Header("retry-after", ""),
      Header("server", ""),
      Header("set-cookie", ""),
      Header("strict-transport-security", ""),
      Header("transfer-encoding", ""),

    assertThat(client.connectionPool.connectionCount()).isEqualTo(2)
    assertThat(server.takeRequest().sequenceNumber)
      .isEqualTo(0) // Fresh connection.
    assertThat(server.takeRequest().sequenceNumber)
      .isEqualTo(0) // Fresh connection.
  }

  /**
   * Check we would use an existing connection to a later DNS result instead of connecting to the
   * first DNS result for the first time.