*
   * <p>The objects returned by consecutive calls to {@link #peek()} then {@link #next()} are
   * guaranteed to be equal to each other.
   */
  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  E next();

  /**
   * {@inheritDoc}
   *
   * <p>Implementations may or may not support removal when a call to {@link #peek()} has occurred
   * since the most recent call to {@link #next()}.
   *

 *
 * ```java
 * Call call = client.newCall(request);
 * call.enqueue(new Callback() {
 *   public void onResponse(Call call, Response response) throws IOException {
 *     try (ResponseBody responseBody = response.body()) {
 *     ... // Use the response.
 *     }
 *   }
 *
 *   public void onFailure(Call call, IOException e) {
 *   ... // Handle the failure.
 *   }
 * });
 * ```
 *

    return capacityWithoutIt >= addressState.policy.minimumConcurrentCalls
  }

  /**
   * Prunes any leaked calls and then returns the number of remaining live calls on [connection].
   * Calls are leaked if the connection is tracking them but the application code has abandoned
   * them. Leak detection is imprecise and relies on garbage collection.
   */

    assertEquals(0, (int) iter.next());

    assertEquals(1, (int) iter.peek());
    assertEquals(1, (int) iter.next());

    /*
     * We test peek() after various calls to make sure that one bad call doesn't interfere with its
     * ability to throw the correct exception in the future.
     */
    assertThrows(NoSuchElementException.class, iter::peek);

  @get:JvmName("certificateChainCleaner")
  val certificateChainCleaner: CertificateChainCleaner?

  /**
   * Default call timeout (in milliseconds). By default there is no timeout for complete calls, but
   * there is for the connect, write, and read actions within a call.
   *
   * For WebSockets and duplex calls the timeout only applies to the initial setup.
   */
  @get:JvmName("callTimeoutMillis")

 * insert a key-value pair with a key that isn't already in the multimap, {@code
 * AbstractMapBasedMultimap} calls {@link #createCollection()} to create the collection of values
 * for that key. The subclass should not call {@link #createCollection()} directly, and a new
 * instance should be created every time the method is called.
 *

                    if (callCount[0] % 2 == 0) {
                        throw new RuntimeException("Even call error");
                    }
                    // Odd calls succeed
                }
            }
        };
        ComponentUtil.register(mockSearchLogHelper, "searchLogHelper");

        // First call (odd) should succeed
        String result1 = aggregateLogJob.execute();
        assertEquals("", result1);

    }

    @Override public void callStart(Call call) {
      printEvent("callStart");
    }

    @Override public void proxySelectStart(Call call, HttpUrl url) {
      printEvent("proxySelectStart");
    }

    @Override public void proxySelectEnd(Call call, HttpUrl url, List<Proxy> proxies) {
      printEvent("proxySelectEnd");
    }

    @Override public void dnsStart(Call call, String domainName) {

  public void testReturning() throws Exception {
    assertNull(Callables.returning(null).call());

    Object value = new Object();
    Callable<Object> callable = Callables.returning(value);
    assertSame(value, callable.call());
    // Expect the same value on subsequent calls
    assertSame(value, callable.call());
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testAsAsyncCallable() throws Exception {

    OkHttp 2 uses the new `Request` class for this.

 *  **Dispatcher** is a new class that manages the queue of asynchronous calls. It
    implements limits on total in-flight calls and in-flight calls per host.

#### Implementation changes

 * Support Android `TrafficStats` socket tagging.
 * Drop authentication headers on redirect.
 * Added support for compressed data frames.