*   <li>awaits executor service termination for half of the specified timeout.
   *   <li>if the timeout expires, it calls {@link ExecutorService#shutdownNow()}, cancelling
   *       pending tasks and interrupting running tasks.
   *   <li>awaits executor service termination for the other half of the specified timeout.
   * </ol>
   *

      } finally {
        lockStateChanged(this);
      }
    }

    @Override
    public boolean tryLock(long timeout, TimeUnit unit) throws InterruptedException {
      aboutToAcquire(this);
      try {
        return super.tryLock(timeout, unit);
      } finally {
        lockStateChanged(this);
      }
    }

    @Override
    public void unlock() {
      try {

   *
   * @param q the blocking queue to be drained
   * @param buffer where to add the transferred elements
   * @param numElements the number of elements to be waited for
   * @param timeout how long to wait before giving up, in units of {@code unit}
   * @param unit a {@code TimeUnit} determining how to interpret the timeout parameter
   * @return the number of elements transferred

    }
  }

  /** Checks that future.get times out, with the default timeout of {@code timeoutMillis()}. */
  void assertFutureTimesOut(Future<?> future) {
    assertFutureTimesOut(future, timeoutMillis());
  }

  /** Checks that future.get times out, with the given millisecond timeout. */
  void assertFutureTimesOut(Future<?> future, long timeoutMillis) {
    long startTime = System.nanoTime();

    // This class can make no hard guarantees.  The methods in this class are inherently flaky, but
    // we try hard to make them robust in practice.  We could additionally try to add in a system
    // load timeout multiplier.  Or we could try to use a CPU time bound instead of wall clock time
    // bound.  But these ideas are harder to implement.  We do not try to detect or handle a
    // user-specified -XX:+DisableExplicitGC.
    //

  @Override
  @ParametricNullness
  public V get(long timeout, TimeUnit unit)
      throws InterruptedException, TimeoutException, ExecutionException {
    // NOTE: if timeout < 0, remainingNanos will be < 0 and we will fall into the while(true) loop
    // at the bottom and throw a timeoutexception.
    final long timeoutNanos = unit.toNanos(timeout); // we rely on the implicit null check on unit.

  // TODO(lukes): Consider throwing InterruptedException when appropriate.
  @Override
  @ParametricNullness
  public V get() {
    return value;
  }

  @Override
  @ParametricNullness
  public V get(long timeout, TimeUnit unit) throws ExecutionException {
    checkNotNull(unit);
    return get();
  }

  @Override
  public boolean isCancelled() {
    return false;
  }

  @Override
  public boolean isDone() {

        return;
      }

      /*
       * If we're about to complete the TimeoutFuture, we want to release our reference to it.
       * Otherwise, we'll pin it (and its result) in memory until the timeout task is GCed. (The
       * need to clear our reference to the TimeoutFuture is the reason we use a *static* nested
       * class with a manual reference back to the "containing" class.)
       *

      return super.get();
    }

    @CanIgnoreReturnValue
    @Override
    public final V get(long timeout, TimeUnit unit)
        throws InterruptedException, ExecutionException, TimeoutException {
      return super.get(timeout, unit);
    }

    @Override
    public final boolean isDone() {
      return super.isDone();
    }

    @Override

    // This class can make no hard guarantees.  The methods in this class are inherently flaky, but
    // we try hard to make them robust in practice.  We could additionally try to add in a system
    // load timeout multiplier.  Or we could try to use a CPU time bound instead of wall clock time
    // bound.  But these ideas are harder to implement.  We do not try to detect or handle a
    // user-specified -XX:+DisableExplicitGC.
    //