![Events Diagram](../assets/images/******@****.***)

Here’s a [sample event listener](https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PrintEventsNonConcurrent.java) that prints each event with a timestamp.

```java
class PrintingEventListener extends EventListener {

include(":okhttp-sse")
include(":okhttp-testing-support")
include(":okhttp-tls")
include(":okhttp-urlconnection")
include(":samples:compare")
include(":samples:crawler")
include(":samples:guide")
include(":samples:simple-client")
include(":samples:slack")
include(":samples:static-server")
include(":samples:tlssurvey")
include(":samples:unixdomainsockets")
include(":container-tests")

project(":okhttp-logging-interceptor").name = "logging-interceptor"

import org.junit.jupiter.params.provider.ArgumentsSource

private val prefix = if (File("samples").exists()) "" else "../../"

private fun mainFiles(): List<File> {
  val directories =
    listOf(
      "$prefix/samples/guide/src/main/java/okhttp3/guide",
      "$prefix/samples/guide/src/main/java/okhttp3/recipes",
      "$prefix/samples/guide/src/main/java/okhttp3/recipes/kt",
    ).map { File(it) }

  return directories.flatMap {

Samples

 [CVE-2021-0341]: https://nvd.nist.gov/vuln/detail/CVE-2021-0341
 [CVE-2022-24329]: https://nvd.nist.gov/vuln/detail/CVE-2022-24329
 [dev_server]: https://github.com/square/okhttp/blob/482f88300f78c3419b04379fc26c3683c10d6a9d/samples/guide/src/main/java/okhttp3/recipes/kt/DevServer.kt
 [fun_interface]: https://kotlinlang.org/docs/reference/fun-interfaces.html
 [iana_websocket]: https://www.iana.org/assignments/websocket/websocket.txt

 [CertificatePinningJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/CertificatePinning.java
 [CertificatePinningKotlin]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/kt/CertificatePinning.kt
 [provider_installer]: https://developer.android.com/training/articles/security-gms-provider

 [changelog]: https://square.github.io/okhttp/changelog/
 [conscrypt]: https://github.com/google/conscrypt/
 [get_example]: https://raw.github.com/square/okhttp/master/samples/guide/src/main/java/okhttp3/guide/GetExample.java
 [kotlin]: https://kotlinlang.org/
 [okhttp3_pro]: https://raw.githubusercontent.com/square/okhttp/master/okhttp/src/main/resources/META-INF/proguard/okhttp3.pro

package okhttp3.sample;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.security.GeneralSecurityException;
import java.security.KeyStore;
import java.security.SecureRandom;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManagerFactory;
import okhttp3.mockwebserver.Dispatcher;

import org.apache.hc.core5.http.ProtocolVersion
import org.junit.Assert
import org.junit.Test

/**
 * Simplified from
 * https://hc.apache.org/httpcomponents-client-5.0.x/httpclient5/examples/AsyncClientTlsAlpn.java
 *
 * Mainly intended to verify behaviour of popular clients across Android versions, similar
 * to observing Firefox or Chrome browser behaviour.
 */
class ApacheHttpClientHttp2Test {
  @Test

import java.io.IOException;
import java.security.cert.Certificate;
import java.security.cert.X509Certificate;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

/**
 * Simple test adaptable to show a failure in older versions of OkHttp
 * or Android SDKs.
 */
@RunWith(AndroidJUnit4.class)
public class IssueReproductionTest {
  @Test public void getFailsWithoutAdditionalCert() throws IOException {