static final class SlowChannel extends AbstractInterruptibleChannel {
    final CountDownLatch exitClose = new CountDownLatch(1);

    @Override
    protected void implCloseChannel() {
      Uninterruptibles.awaitUninterruptibly(exitClose);
    }

    void doBegin() {
      super.begin();
    }
  }

                // to
                // ensure that the thread running the failure callbacks is not the main thread.
                Uninterruptibles.awaitUninterruptibly(afterStarted);
                notifyFailed(new Exception("boom"));
              }
            }.start();
          }

          @Override
          protected void doStop() {

          // do nothing
        } finally {
          completedIteration.countDown();
        }
      }
    }

    void awaitInLoop() {
      Uninterruptibles.awaitUninterruptibly(completedIteration);
    }
  }

  private static final class InterruptibleFuture extends AbstractFuture<String> {
    boolean interruptTaskWasCalled;

    @Override

          // do nothing
        } finally {
          completedIteration.countDown();
        }
      }
    }

    void awaitInLoop() {
      Uninterruptibles.awaitUninterruptibly(completedIteration);
    }
  }

  private static final class InterruptibleFuture extends AbstractFuture<String> {
    boolean interruptTaskWasCalled;

    @Override