private OverflowAvoidingLockSupport() {}

  static void parkNanos(@CheckForNull Object blocker, long nanos) {
    // Even in the extremely unlikely event that a thread unblocks itself early after only 68 years,
    // this is indistinguishable from a spurious wakeup, which LockSupport allows.
    LockSupport.parkNanos(blocker, min(nanos, MAX_NANOSECONDS_THRESHOLD));
  }

          interrupted = true;
        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
  }

  /** Unblocks all threads and runs all listeners. */
  private static void complete(AbstractFuture<?> param, boolean callInterruptTask) {
    // Declare a "true" local variable so that the Checker Framework will infer nullness.