* Clears fields that are no longer needed after this future has completed -- or at least all its
   * inputs have completed (more precisely, after {@link #handleAllCompleted()} has been called).
   * Often called multiple times (that is, both when the inputs complete and when the output
   * completes).
   *
   * <p>This is similar to our proposed {@code afterCommit} method but not quite the same. See the
   * description of CL 265462958.
   */

      assertTrue(queue.offer("blocksPutCallsUntilRemoved"));
      this.completed = new Completion(countdownInMillis);
      scheduleEnableWrites(this.queue, countdownInMillis);
    }

    /** Perform a {@code put} and assert that operation completed in the expected timeframe. */
    void putSuccessfully() {
      putUninterruptibly(queue, "");
      completed.assertCompletionExpected();
      assertEquals("", queue.peek());
    }

      }

      /** Transition to the COMPLETED state and set the value. */
      boolean set(@Nullable V v) {
        return complete(v, null, COMPLETED);
      }

      /** Transition to the COMPLETED state and set the exception. */
      boolean setException(Throwable t) {
        return complete(null, t, COMPLETED);
      }

      /** Transition to the CANCELLED or INTERRUPTED state. */

      }

      /** Transition to the COMPLETED state and set the value. */
      boolean set(@Nullable V v) {
        return complete(v, null, COMPLETED);
      }

      /** Transition to the COMPLETED state and set the exception. */
      boolean setException(Throwable t) {
        return complete(null, t, COMPLETED);
      }

      /** Transition to the CANCELLED or INTERRUPTED state. */

      assertTrue(queue.offer("blocksPutCallsUntilRemoved"));
      this.completed = new Completion(countdownInMillis);
      scheduleEnableWrites(this.queue, countdownInMillis);
    }

    /** Perform a {@code put} and assert that operation completed in the expected timeframe. */
    void putSuccessfully() {
      putUninterruptibly(queue, "");
      completed.assertCompletionExpected();
      assertEquals("", queue.peek());
    }

 *       be "done" as soon as <i>that</i> {@code Future} completes in any way. Notably, a {@code
 *       Future} is "completed" even if it is cancelled while its underlying work continues on a
 *       thread, an RPC, etc. The {@code Future} is also "completed" if it fails "early" -- for
 *       example, if the deadline expires on a {@code Future} returned from {@link

              }
            }
          });
      executor.execute(
          new Runnable() {
            @Override
            public void run() {
              future.cancel(true);
              if (!future.isDone()) {
                errorMessage.set("Cancel call exited before future was complete.");
              }
            }
          });

  }

  public void testListeningDecorator_scheduleSuccess() throws Exception {
    final CountDownLatch completed = new CountDownLatch(1);
    ScheduledThreadPoolExecutor delegate =
        new ScheduledThreadPoolExecutor(1) {
          @Override
          protected void afterExecute(Runnable r, Throwable t) {
            completed.countDown();
          }
        };

              }
            }
          });
      executor.execute(
          new Runnable() {
            @Override
            public void run() {
              future.cancel(true);
              if (!future.isDone()) {
                errorMessage.set("Cancel call exited before future was complete.");
              }
            }
          });

   * computation is {@linkplain java.util.concurrent.Future#isDone() complete} or, if the
   * computation is already complete, immediately.
   *
   * <p>The callback is run on {@code executor}. There is no guaranteed ordering of execution of
   * callbacks, but any callback added through this method is guaranteed to be called once the
   * computation is complete.
   *
   * <p>Example:
   *
   * <pre>{@code