} finally {
        unlock();
        postWriteCleanup();
      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

        new Runnable() {
          @Override
          public void run() {
            awaitUninterruptibly(beforeFunction);
          }
        });

    // Cancel the future after making input available.
    inputFuture.set("value");
    future.cancel(false);

    // Unpause the executor.
    beforeFunction.countDown();
    executor.shutdown();
    assertTrue(executor.awaitTermination(5, SECONDS));

        new Runnable() {
          @Override
          public void run() {
            awaitUninterruptibly(beforeFunction);
          }
        });

    // Cancel the future after making input available.
    inputFuture.set("value");
    future.cancel(false);

    // Unpause the executor.
    beforeFunction.countDown();
    executor.shutdown();
    assertTrue(executor.awaitTermination(5, SECONDS));

      } finally {
        unlock();
        postWriteCleanup();
      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @SuppressWarnings({"AndroidJdkLibsChecker", "Java7ApiChecker"})
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  @Beta // TODO: b/288085449 - Remove.

 *       can be captured for later closing.
 *   <li>There is one last step (the root of the tree), from which you can extract the final result
 *       of the computation. After that result is available (or the computation fails), all objects
 *       captured by any of the steps in the pipeline are closed.
 * </ol>
 *
 * <h3>Starting a pipeline</h3>
 *