We highly recommend you keep OkHttp up-to-date. As with auto-updating web browsers, staying current
with HTTPS clients is an important defense against potential security problems. [We
track][tls_history] the dynamic TLS ecosystem and adjust OkHttp to improve connectivity and
security.

OkHttp uses your platform's built-in TLS implementation. On Java platforms OkHttp also supports

Interceptors can be chained. Suppose you have both a compressing interceptor and a checksumming interceptor: you'll need to decide whether data is compressed and then checksummed, or checksummed and then compressed. OkHttp uses lists to track interceptors, and interceptors are called in order.

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

### Application Interceptors

    different from the version that the module was compiled with. Do not use them in published
    libraries. Do not use them if you aren't willing to track changes to them.

 *  Breaking: Drop support for Kotlin Multiplatform.

    We planned to support multiplatform in OkHttp 5.0, but after building it, we weren't happy with

TLS Configuration History
=========================

OkHttp tracks the dynamic TLS ecosystem to balance connectivity and security. This page is a log of
changes we've made over time to OkHttp's default TLS options.

[OkHttp 3.14][OkHttp314]
------------------------

_2019-03-14_

Remove 2 TLSv1.3 cipher suites that are neither available on OkHttp’s host platforms nor enabled in releases of Chrome and Firefox.

##### RESTRICTED_TLS cipher suites

 * the version the module was compiled with.
 *
 * Do not use these APIs in published libraries.
 *
 * Do not use these APIs if you aren't willing to track changes to them.
 */
@MustBeDocumented
@Retention(value = AnnotationRetention.BINARY)
@Target(
  AnnotationTarget.CLASS,
  AnnotationTarget.ANNOTATION_CLASS,
  AnnotationTarget.PROPERTY,
  AnnotationTarget.FIELD,

            call.executeAsync()
          }
        }
      }

      assertThat(call.canceled).isTrue()
      assertThat(call.responseClosed).isTrue()
    }
  }

  /** A call that keeps track of whether its response body is closed. */
  private class ClosableCall : FailingCall() {
    private val response =
      Response.Builder()
        .request(Request("https://example.com/".toHttpUrl()))

   *
   *   o DIRTY lines track that an entry is actively being created or updated. Every successful
   *     DIRTY action should be followed by a CLEAN or REMOVE action. DIRTY lines without a matching
   *     CLEAN or REMOVE indicate that temporary files may need to be deleted.
   *
   *   o CLEAN lines track a cache entry that has been successfully published and may be read. A

 * `CLEARTEXT` is an insecure configuration that is used for `http://` URLs.

These loosely follow the model set in [Google Cloud Policies](https://cloud.google.com/load-balancing/docs/ssl-policies-concepts). We [track changes](../security/tls_configuration_history.md) to this policy.

      DerHeader(
        tagClass = DerHeader.TAG_CLASS_UNIVERSAL,
        tag = DerHeader.TAG_END_OF_CONTENTS,
        constructed = false,
        length = -1L,
      )
  }

  /** A source that keeps track of how many bytes it's consumed. */
  private class CountingSource(source: Source) : ForwardingSource(source) {
    var bytesRead = 0L

    override fun read(
      sink: Buffer,
      byteCount: Long,

    )
  }

  /**
   * The runner doesn't hold references to its queues! Otherwise we'd need a mechanism to clean them
   * up when they're no longer needed and that's annoying. Instead the task runner only tracks which
   * queues have work scheduled.
   */
  @Test fun activeQueuesContainsOnlyQueuesWithScheduledTasks() {
    redQueue.execute("task one", 100.µs) {
      // Do nothing.
    }