SAM Conversions
---------------

When you use Java APIs from Kotlin you can operate on Java interfaces as if they were Kotlin
lambdas. The [feature][java_sams] is available for interfaces that define a Single Abstract Method
(SAM).

But when you use Kotlin APIs from Kotlin there’s no automatic conversion. Code that used SAM lambdas
with OkHttp 3.x: must use `object :` with OkHttp 4.x:

Kotlin calling OkHttp 3.x:

  @ValueSource(booleans = [false, true])
  fun proxyMoveTest(cleanShutdown: Boolean) {
    // Define a single Proxy at myproxy:8008 that will artificially move during the test
    val proxySelector = RecordingProxySelector()
    proxySelector.proxies.add(Proxy(Proxy.Type.HTTP, InetSocketAddress("myproxy", 8008)))

    // Define two host names for the DNS routing of fake proxy servers

    val client = makeClient()
    makeRequest(client)

    // As of OkHttp 5 we now apply the ordering from the OkHttpClient, which defaults to MODERN_TLS
    // Clients might need a changed order, but can at least define a preferred order to override that default.
    val socketOrderedByDefaults =
      handshakeEnabledCipherSuites.sortedBy { ConnectionSpec.MODERN_TLS.cipherSuitesAsString!!.indexOf(it) }

`MultipartBody.Builder` can build sophisticated request bodies compatible with HTML file upload forms. Each part of a multipart request body is itself a request body, and can define its own headers. If present, these headers should describe the part body, such as its `Content-Disposition`. The `Content-Length` and `Content-Type` headers are added automatically if they're available.

    open fun headers(headers: Headers) = commonHeaders(headers)

    /**
     * Sets this request's `Cache-Control` header, replacing any cache control headers already
     * present. If [cacheControl] doesn't define any directives, this clears this request's
     * cache-control headers.
     */
    open fun cacheControl(cacheControl: CacheControl): Builder = commonCacheControl(cacheControl)

   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

   1. Definitions.

      "License" shall mean the terms and conditions for use, reproduction,
      and distribution as defined by Sections 1 through 9 of this document.

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

 *
 * > A DNS API client encodes a single DNS query into an HTTP request
 * > using either the HTTP GET or POST method and the other requirements
 * > of this section.  The DNS API server defines the URI used by the
 * > request through the use of a URI Template.
 *
 * [doh_spec]: https://tools.ietf.org/html/draft-ietf-doh-dns-over-https-13
 */
class DnsOverHttps internal constructor(

    // OkHttp 2.x:
    HttpURLConnection connection = new OkUrlFactory(client).open(url);
    ```

 *  **Custom caches are no longer supported.** In OkHttp 1.x it was possible to
    define your own response cache with the `java.net.ResponseCache` and OkHttp's
    `OkResponseCache` interfaces. Both of these APIs have been dropped. In
    OkHttp 2 the built-in disk cache is the only supported response cache.

        }

        else -> throw IOException("Unexpected response code for CONNECT: ${response.code}")
      }
    }
  }

  /**
   * Returns this if its [connectionSpecIndex] is defined, or a new connection with it defined
   * otherwise.
   */
  @Throws(IOException::class)
  internal fun planWithCurrentOrInitialConnectionSpec(
    connectionSpecs: List<ConnectionSpec>,
    sslSocket: SSLSocket,

   * the already-requested ones are in service, otherwise we might create more threads than we need.
   *
   * We use [executeCallCount] and [runCallCount] to defend against starting more threads than we
   * need. Both fields are guarded by [lock].
   */
  private var executeCallCount = 0
  private var runCallCount = 0