Assert.fail("This call was supposed to throw an ExecutionException");
    } catch (ExecutionException expected) {
      Assert.assertSame(expectedCause, expected.getCause());
    }
  }

  public void assertTimeout() throws Exception {
    // Verify that the listener does not get called in a reasonable amount of
    // time.
    Assert.assertFalse(countDownLatch.await(1L, SECONDS));
  }