List<Object> buf = new ArrayList<>();
      int elements = drain(q, buf, 100, MAX_VALUE, NANOSECONDS, interruptibly);
      assertEquals(100, elements);
      assertEquals(100, buf.size());
      assertDrained(q);
    }
  }

  public void testDrainTimesOut() throws Exception {
    for (BlockingQueue<Object> q : blockingQueues()) {
      checkDrainTimesOut(q);
    }
  }