object : Task("task one") {
        val schedules = mutableListOf(200.µs)

        override fun runOnce(): Long {
          if (schedules.isNotEmpty()) {
            redQueue.schedule(this, schedules.removeAt(0)) // Add it at the end also.
          }
          log += "scheduledTasks=${redQueue.scheduledTasks}"
          return -1L
        }
      }
    redQueue.schedule(task, 100.µs)

    // If the task is already scheduled, take the earlier of the two times.
    val existingIndex = futureTasks.indexOf(task)
    if (existingIndex != -1) {
      if (task.nextExecuteNanoTime <= executeNanoTime) {
        taskRunner.logger.taskLog(task, this) { "already scheduled" }
        return false
      }
      futureTasks.removeAt(existingIndex) // Already scheduled later: reschedule below!
    }

      private ScheduledFuture<@Nullable Void> submitToExecutor(Schedule schedule) {
        return executor.schedule(this, schedule.delay, schedule.unit);
      }
    }

    /**
     * Contains the most recently submitted {@code Future}, which may be cancelled or updated,
     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      private ScheduledFuture<@Nullable Void> submitToExecutor(Schedule schedule) {
        return executor.schedule(this, schedule.delay, schedule.unit);
      }
    }

    /**
     * Contains the most recently submitted {@code Future}, which may be cancelled or updated,
     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

│   └── job/                   # Background jobs
├── api/                       # REST API endpoints
├── opensearch/                # OpenSearch integration
│   ├── config/                # Config index (crawl configs, schedules)
│   ├── log/                   # Log index
│   ├── user/                  # User index
│   ├── exbhv/                 # Extended behaviors (repositories)
│   └── exentity/              # Extended entities (domain models)

        this.asyncNotifyTasks = new ConcurrentHashMap<>();
        this.scheduler = Executors.newScheduledThreadPool(3); // Increased for async notifications
        this.rpcClient = rpcClient;

        // Schedule periodic tasks
        schedulePeriodicTasks();
    }

    /**
     * Schedules periodic tasks for heartbeat and registration monitoring.
     */

   *     remote server accepted the request before the failure.
   * @throws IllegalStateException when the call has already been executed.
   */
  @Throws(IOException::class)
  fun execute(): Response

  /**
   * Schedules the request to be executed at some point in the future.
   *
   * The [dispatcher][OkHttpClient.dispatcher] defines when the request will run: usually

    Future<?> scheduled = executorService.schedule(task, delay, timeUnit);
    /*
     * Even when the user interrupts the task, we pass `false` to `cancel` so that we don't
     * interrupt a second time after the interruption performed by TrustedListenableFutureTask.
     */
    task.addListener(() -> scheduled.cancel(false), directExecutor());
    return task;
  }

  /**

### Go-Live

- [ ] Schedule maintenance window
- [ ] Final incremental data sync
- [ ] Switch DNS or endpoints to Fess
- [ ] Monitor logs for errors
- [ ] Monitor search performance metrics
- [ ] Have rollback plan ready

### Post-Migration

- [ ] Monitor search quality and relevance
- [ ] Tune ranking and boosting settings
- [ ] Set up regular crawl schedules
- [ ] Configure backup and disaster recovery

            }
        } catch (final IOException e) {
            logger.warn("Failed to access groups/roles in Entra ID.", e);
        }
    }

    /**
     * Schedules asynchronous parent group lookup using TimeoutManager.
     * This method defers the retrieval of nested group information to avoid login delays.
     * @param user The Entra ID user.