5. It sends the HTTP request and reads the response.

  @Throws(IOException::class)
  fun plan(): Plan

  /**
   * Returns true if there's more route plans to try.
   *
   * @param failedConnection an optional connection that was resulted in a failure. If the failure
   *     is recoverable, the connection's route may be recovered for the retry.
   */
  fun hasNext(failedConnection: RealConnection? = null): Boolean

  /**

    call: Call,
    inetSocketAddress: InetSocketAddress,
    proxy: Proxy,
    protocol: Protocol?,
  ) {
  }

  /**
   * Invoked when a connection attempt fails. This failure is not terminal if further routes are
   * available and failure recovery is enabled.
   *
   * If the `call` uses HTTPS, this will be invoked after [secureConnectStart], otherwise it will
   * invoked after [connectStart].
   */

        assertThat(throwables!!.size).isEqualTo(1)
      }
    }
  }

  /**
   * When a pooled connection fails, don't blame the route. Otherwise pooled connection failures can
   * cause unnecessary SSL fallbacks.
   *
   * https://github.com/square/okhttp/issues/515
   */
  @Test
  fun sslFallbackNotUsedWhenRecycledConnectionFails() {

 *  New: `HttpLoggingInterceptor` now logs connection failures.
 *  New: Upgrade to Okio 1.8.0.

     ```xml
     <dependency>
       <groupId>com.squareup.okio</groupId>
       <artifactId>okio</artifactId>
       <version>1.8.0</version>
     </dependency>
     ```

 *  Fix: Gracefully recover from a failure to rebuild the cache journal.

    } catch (e: Exception) {
      synchronized(failures) {
        failures.add(e)
      }
    }
  }

  @Throws(UnknownHostException::class)
  private fun throwBestFailure(
    hostname: String,
    failures: List<Exception>,
  ): List<InetAddress> {
    if (failures.isEmpty()) {
      throw UnknownHostException(hostname)
    }

    val failure = failures[0]

    if (failure is UnknownHostException) {

    server.enqueue(MockResponse(socketPolicy = DisconnectAtStart))

    client =
      client.newBuilder()
        .dns(DoubleInetAddressDns()) // Two routes so we get two failures.
        .build()

    val request = Request(server.url("/"))
    assertFailsWith<IOException> {
      client.newCall(request).execute()
    }.also { expected ->
      expected.assertSuppressed {

      }
    }
  }

  /**
   * Report and attempt to recover from a failure to communicate with a server. Returns true if
   * `e` is recoverable, or false if the failure is permanent. Requests with a body can only
   * be recovered if the body is buffered or if the failure occurred before the request has been
   * sent.
   */
  private fun recover(
    e: IOException,

     *   connection.
     *
     * Set this to false to avoid retrying requests when doing so is destructive. In this case the
     * calling application should do its own recovery of connectivity failures.
     */
    fun retryOnConnectionFailure(retryOnConnectionFailure: Boolean) =
      apply {
        this.retryOnConnectionFailure = retryOnConnectionFailure
      }

    /**

    check(rule.startsWith(WILDCARD_CHAR)) {
      """Wildcard Assertion Failure: '$rule'
A wildcard rule was added with a wildcard that is not in leftmost position! We'll need to change the ${PublicSuffixDatabase::class.java.name} to handle this."""
    }
    check(rule.indexOf(WILDCARD_CHAR, 1) == -1) {
      """Wildcard Assertion Failure: '$rule'