// Call the next interceptor in the chain.
    val next = copy(index = index + 1, request = request)
    val interceptor = interceptors[index]

    @Suppress("USELESS_ELVIS")
    val response =
      interceptor.intercept(next) ?: throw NullPointerException(
        "interceptor $interceptor returned null",
      )

    if (exchange != null) {
      check(index + 1 >= interceptors.size || next.calls == 1) {

    // Build a full stack of interceptors.
    val interceptors = mutableListOf<Interceptor>()
    interceptors += client.interceptors
    interceptors += RetryAndFollowUpInterceptor()
    interceptors += BridgeInterceptor()
    interceptors += CacheInterceptor()
    interceptors += ConnectInterceptor
    if (!forWebSocket) {
      interceptors += client.networkInterceptors
    }

    running SSLv3, you must manually configure your own `ConnectionSpec`.

 *  **OkHttp now offers interceptors.** Interceptors are a powerful mechanism
    that can monitor, rewrite, and retry calls. The [interceptors doc][interceptors] is a full
    introduction to this new API.

 *  New: APIs to iterate and selectively clear the response cache.
 *  New: Support for SOCKS proxies.

     * [Request.tag]. Use null to remove any existing tag assigned for [T].
     *
     * Use this API to attach timing, debugging, or other application data to a request so that
     * you may read it in interceptors, event listeners, or callbacks.
     */
    @JvmName("reifiedTag")
    inline fun <reified T : Any> tag(tag: T?): Builder = tag(T::class, tag)

    /**

Cleanup_ for a safe and fast upgrade.


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

      }
    val interceptor2 =
      Interceptor { chain: Interceptor.Chain ->
        assertThat(chain.writeTimeoutMillis()).isEqualTo(100)
        chain.proceed(chain.request())
      }
    client =
      client
        .newBuilder()
        .writeTimeout(Duration.ofSeconds(5))
        .addInterceptor(interceptor1)
        .addInterceptor(interceptor2)
        .build()
    server.enqueue(

    val proxy: Proxy? = client.proxy()
    val protocols: List<Protocol> = client.protocols()
    val connectionSpecs: List<ConnectionSpec> = client.connectionSpecs()
    val interceptors: List<Interceptor> = client.interceptors()
    val networkInterceptors: List<Interceptor> = client.networkInterceptors()
    val eventListenerFactory: EventListener.Factory = client.eventListenerFactory()
    val proxySelector: ProxySelector = client.proxySelector()

      .newClientBuilder()
      .writeTimeout(Duration.ofMillis(500))
      .readTimeout(Duration.ofMillis(500))
      .addInterceptor(
        Interceptor { chain: Interceptor.Chain ->
          val response = chain.proceed(chain.request())
          // Ensure application interceptors never see a null body.
          assertThat(response.body).isNotNull()
          response
        },
      ).build()

    assertThat(client.connectionPool.connectionCount()).isEqualTo(1)
  }

  /** Network interceptors check for changes to target.  */
  @Test
  fun worksWithNetworkInterceptors() {
    client =
      client
        .newBuilder()
        .addNetworkInterceptor(
          Interceptor { chain: Interceptor.Chain? ->
            chain!!.proceed(
              chain.request(),
            )
          },

  /**
   * The request that initiated this HTTP response. This is not necessarily the same request issued
   * by the application:
   *
   * * It may be transformed by the user's interceptors. For example, an application interceptor
   *   may add headers like `User-Agent`.
   * * It may be the request generated in response to an HTTP redirect or authentication