this.fastFallback = okHttpClient.fastFallback
      this.authenticator = okHttpClient.authenticator
      this.followRedirects = okHttpClient.followRedirects
      this.followSslRedirects = okHttpClient.followSslRedirects
      this.cookieJar = okHttpClient.cookieJar
      this.cache = okHttpClient.cache
      this.dns = okHttpClient.dns
      this.proxy = okHttpClient.proxy
      this.proxySelector = okHttpClient.proxySelector

import java.net.UnknownHostException
import okhttp3.HttpUrl.Companion.toHttpUrl
import okhttp3.OkHttpClient

/**
 * Temporary registry of known DNS over HTTPS providers.
 *
 * https://github.com/curl/curl/wiki/DNS-over-HTTPS
 */
object DohProviders {
  private fun buildGoogle(bootstrapClient: OkHttpClient): DnsOverHttps {
    return DnsOverHttps.Builder()
      .client(bootstrapClient)

      )
    }
  }

  @Test fun testH2PriorKnowledgeOkHttpClientConstructionSuccess() {
    val okHttpClient =
      OkHttpClient.Builder()
        .protocols(listOf(Protocol.H2_PRIOR_KNOWLEDGE))
        .build()
    assertThat(okHttpClient.protocols.size).isEqualTo(1)
    assertThat(okHttpClient.protocols[0]).isEqualTo(Protocol.H2_PRIOR_KNOWLEDGE)
  }

  @Test fun nullDefaultProxySelector() {

    ```java
      private final OkHttpClient client = new OkHttpClient();

      public void run() throws Exception {
        Request request = new Request.Builder()
            .url("http://httpbin.org/delay/1") // This URL is served with a 1 second delay.
            .build();

        // Copy to customize OkHttp for this request.
        OkHttpClient client1 = client.newBuilder()

 */
@RunWith(AndroidJUnit4.class)
public class IssueReproductionTest {
  @Test public void getFailsWithoutAdditionalCert() throws IOException {
    OkHttpClient client = new OkHttpClient();

    sendRequest(client, "https://google.com/robots.txt");
  }

  private void sendRequest(OkHttpClient client, String url) throws IOException {
    Request request = new Request.Builder()
            .url(url)
            .build();

Entrust and Verisign.

This is the behavior you'll get with your OkHttpClient if you don't specifically configure
`HandshakeCertificates`. Or you can do it explicitly with `addPlatformTrustedCertificates()`:

```java
HandshakeCertificates clientCertificates = new HandshakeCertificates.Builder()
    .addPlatformTrustedCertificates()
    .build();
OkHttpClient client = new OkHttpClient.Builder()

 * for background.
 */
@RunWith(AndroidJUnit4.class)
public class LetsEncryptTest {
  @Test public void getFailsWithoutAdditionalCert() throws IOException {
    OkHttpClient client = new OkHttpClient();

    boolean androidMorEarlier = Build.VERSION.SDK_INT <= 23;
    try {
      sendRequest(client, "https://valid-isrgrootx1.letsencrypt.org/robots.txt");
      if (androidMorEarlier) {
        fail();

 */
package okhttp3.brotli

import okhttp3.OkHttpClient
import okhttp3.Request

fun main() {
  val client =
    OkHttpClient.Builder()
      .addInterceptor(BrotliInterceptor)
      .build()

  sendRequest("https://httpbin.org/brotli", client)
  sendRequest("https://httpbin.org/gzip", client)
}

private fun sendRequest(
  url: String,
  client: OkHttpClient,
) {
  val req = Request.Builder().url(url).build()

Backwards-Incompatible Changes
------------------------------

#### OkHttpClient final methods

`OkHttpClient` has 26 accessors like `interceptors()` and `writeTimeoutMillis()` that were non-final
in OkHttp 3.x and are final in 4.x. These were made non-final for use with mocking frameworks like
[Mockito][mockito]. We believe subtyping `OkHttpClient` is the wrong way to test with OkHttp. If

package okhttp3

import java.io.IOException
import okhttp3.Authenticator.Companion.JAVA_NET_AUTHENTICATOR

/**
 * Do not use this.
 *
 * Instead, configure your OkHttpClient.Builder to use `Authenticator.JAVA_NET_AUTHENTICATOR`:
 *
 * ```
 *   val okHttpClient = OkHttpClient.Builder()
 *     .authenticator(okhttp3.Authenticator.Companion.JAVA_NET_AUTHENTICATOR)
 *     .build()
 * ```
 */