Calls are executed in one of two ways:

 * **Synchronous:** your thread blocks until the response is readable.
 * **Asynchronous:** you enqueue the request on any thread, and get [called back](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-callback/) on another thread when the response is readable.

package okhttp3.internal.concurrent

import assertk.assertThat
import assertk.assertions.isCloseTo
import assertk.assertions.isEmpty
import assertk.assertions.isEqualTo
import assertk.assertions.isTrue
import java.lang.Thread.UncaughtExceptionHandler
import java.util.concurrent.LinkedBlockingDeque
import java.util.concurrent.ThreadFactory
import java.util.concurrent.TimeUnit
import org.junit.jupiter.api.AfterEach
import org.junit.jupiter.api.Tag

    assertThat(realTaskRunner.activeQueues()).isNotEmpty()
    Thread.sleep(100)
    val threads = arrayOfNulls<Thread>(Thread.activeCount() * 2)
    Thread.enumerate(threads)
    for (t in threads) {
      if (t != null && t.name == "OkHttp TaskRunner") {
        t.interrupt()
      }
    }
    Thread.sleep(100)
    assertThat(realTaskRunner.activeQueues()).isEmpty()
  }

      Request.Builder()
        .url(server.url("/"))
        .build()
    val call = client.newCall(request)
    call.timeout().timeout(250, TimeUnit.MILLISECONDS)
    val response = call.execute()
    Thread.sleep(500)
    assertFailsWith<IOException> {
      response.body.source().readUtf8()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("timeout")
      assertThat(call.isCanceled()).isTrue()

  }

  private fun makeSynchronousCall(call: Call): Thread {
    val thread =
      Thread {
        try {
          call.execute()
          throw AssertionError()
        } catch (expected: IOException) {
        }
      }
    thread.start()
    return thread
  }

  private fun newRequest(url: String): Request {
    return Request.Builder().url(url).build()

 *
 *   public void onFailure(Call call, IOException e) {
 *   ... // Handle the failure.
 *   }
 * });
 * ```
 *
 * These examples will not work if you're consuming the response body on another thread. In such
 * cases the consuming thread must call [close] when it has finished reading the response
 * body.
 *
 * ### The response body can be consumed only once.
 *

        .build(),
    )
    val webSocket: WebSocket = newWebSocket()
    clientListener.assertOpen()
    val server = serverListener.assertOpen()

    // Sleep longer than the HTTP client's read timeout.
    Thread.sleep((client.readTimeoutMillis + 500).toLong())
    server.send("abc")
    clientListener.assertTextMessage("abc")
    closeWebSockets(webSocket, server)
  }

  @Test
  @Throws(Exception::class)

## Version 1.5.3

_2014-03-29_

 * Fix bug where the Content-Length header was not always dropped when
   following a redirect from a POST to a GET.
 * Implement basic support for `Thread.interrupt()`. OkHttp now checks
   for an interruption before doing a blocking call. If it is interrupted,
   it throws an `InterruptedIOException`.

## Version 1.5.2

_2014-03-17_

    `NullPointerException` or `OutOfMemoryError`. We now call `Callback.onFailure()` with an
    `IOException` that reports the call as canceled. The triggering exception is still delivered to
    the thread's `UncaughtExceptionHandler`.
 *  Fix: Don't evict incomplete entries when iterating the cache. We had a bug where iterating
    `Cache.urls()` would prevent in-flight entries from being written.


## Version 3.14.3

  @Throws(InterruptedException::class, TimeoutException::class)
  private fun waitForConnectionShutdown(connection: RealConnection?) {
    if (connection!!.isHealthy(false)) {
      Thread.sleep(100L)
    }
    if (connection.isHealthy(false)) {
      Thread.sleep(2000L)
    }
    if (connection.isHealthy(false)) {
      throw TimeoutException("connection didn't shutdown within timeout")
    }
  }

  /**