Method called once every second by the scheduled job.

@see #start(ScheduledExecutorService)
1342
@SuppressWarnings( "fallthrough" )
    private void rollup() {
        DateTime now = timeFactory.create();
        Window largest = null;
        for (DurationHistory history : durations.values()) {
            largest = history.rollup();
        }
        for (ValueHistory history : values.values()) {
            largest = history.rollup();
        }
        if ( largest == null ) return;
        // Note that we do expect to fall through, as the 'largest' represents the largest window that was changed,
        // while all smaller windows were also changed ...
        switch (largest) {
            case PREVIOUS_52_WEEKS:
                this.weeksStartTime.set(now);
                // fall through!!
            case PREVIOUS_7_DAYS:
                this.daysStartTime.set(now);
                // fall through!!
            case PREVIOUS_24_HOURS:
                this.hoursStartTime.set(now);
                // fall through!!
            case PREVIOUS_60_MINUTES:
                this.minutesStartTime.set(now);
                // fall through!!
            case PREVIOUS_60_SECONDS:
                this.secondsStartTime.set(now);
        }
    }
973966
@Override
    public void start(Supplier<ExecutorService> executorFactory) throws IOException
    {
        future = executorFactory.get().submit(this);
    }
900535
@Override
  public void start() throws SchedulerException {

    if (shuttingDown || closed) {
      throw new SchedulerException(
          "The Scheduler cannot be restarted after shutdown() has been called.");
    }

    if (initialStart == null) {
      initialStart = new Date();
      quartzSchedulerResources.getJobStore().schedulerStarted();
      startPlugins();
    }

    this.quartzSchedulerThread.togglePause(false);

    logger.info("Scheduler started.");

    notifySchedulerListenersStarted();
  }
475144
public void start() {
        logger.info("Started AWSCloudTrailProcessingLibrary.");
        validateBeforeStart();
        scheduledThreadPool.scheduleAtFixedRate(new ScheduledJob(readerFactory), 0L, EXECUTION_DELAY, TimeUnit.MICROSECONDS);
    }
652645
@LifecycleStart
  @Override
  public void start() throws Exception
  {
    super.start();

    synchronized (lifecycleLock) {
      Preconditions.checkState(!started, "already started");
      started = true;

      try {
        cleanupStaleAnnouncements();
        registerRunListener();
        pathChildrenCache.start();

        log.info("Started WorkerTaskMonitor.");
        started = true;
      }
      catch (InterruptedException e) {
        throw e;
      }
      catch (Exception e) {
        log.makeAlert(e, "Exception starting WorkerTaskMonitor")
           .emit();
        throw e;
      }
    }
  }
537548
@Override public void start(Set<File> files, Consumer<Set<File>> callback) {
        if (isStarted()) {
            throw new IllegalStateException("start() should not be called more than once");
        }
        Set<File> filesCopy = ImmutableSet.copyOf(files);
        Preconditions.checkArgument(filesCopy.size() > 0, "must specify at least 1 file to watch for changes");
        this.callback = requireNonNull(callback);
        watchedFiles = filesCopy;
        executorService = MoreExecutors.listeningDecorator(Executors.newScheduledThreadPool(1));
        future = executorService.scheduleAtFixedRate(
            this::scanFilesForChanges,
            initialDelay,
            interval,
            timeUnit);
    }
1159953
public void start() throws Exception
    {
        Preconditions.checkState(state.compareAndSet(State.LATENT, State.STARTED), "Cannot be started more than once");

        task = executor.scheduleWithFixedDelay
        (
            new Runnable()
            {
                @Override
                public void run()
                {
                    doWork();
                }
            },
            reapingThresholdMs,
            reapingThresholdMs,
            TimeUnit.MILLISECONDS
        );
        if (leaderLatch != null)
        {
            leaderLatch.start();
        }
        reaper.start();
    }
823125
@Validate
    public void start() {
        metrics.register("executors", new MetricSet() {
            @Override
            public Map<String, Metric> getMetrics() {
                return ImmutableMap.<String, Metric>of(
                        "executors.count", new Gauge<Integer>() {
                            @Override
                            public Integer getValue() {
                                return getExecutors().length;
                            }
                        },
                        "schedulers.count", new Gauge<Integer>() {

                            @Override
                            public Integer getValue() {
                                return getSchedulers().length;
                            }
                        },
                        "hung.count", new Gauge<Integer>() {

                            @Override
                            public Integer getValue() {
                                return getHungTasks();
                            }
                        },
                        "completed.count", new Gauge<Integer>() {

                            @Override
                            public Integer getValue() {
                                return getCompletedTasks();
                            }
                        }
                );
            }
        });

        for (ManagedExecutorService service : executors) {
            metrics.register(service.name(), metricsForExecutor(service));
        }

        for (ManagedExecutorService service : schedulers) {
            metrics.register(service.name(), metricsForExecutor(service));
        }
    }
787714
def _start(self):
        """"""
        if len(self._queue) == 1:
            thread = self._queue.popleft()
            thread.start()
            self._timer.start()
890810
public void start(final Date start) {
		if (start != null) {
			counter.increment();
			timer.start(start);
		}
	}
358319
@Override
    public void run() {
        final ScheduledFuture<?> future = this.executor.scheduleWithFixedDelay(this.scheduled, 0, this.delayMillis,
                TimeUnit.MILLISECONDS);
        try {
            this.runTrigger.await();
        } catch (final InterruptedException e) {
            this.listener.handle(e);
        } finally {
            future.cancel(true); // stop the periodic reading
            this.scheduled.cleanup();
            this.executor.shutdownNow();
            this.listener.destroy();
        }
    }
1014911
public void start() {
        switch (WORKER_STATE_UPDATER.get(this)) {
            case WORKER_STATE_INIT:
                if (WORKER_STATE_UPDATER.compareAndSet(this, WORKER_STATE_INIT, WORKER_STATE_STARTED)) {
                    workerThread.start();
                }
                break;
            case WORKER_STATE_STARTED:
                break;
            case WORKER_STATE_SHUTDOWN:
                throw new IllegalStateException("cannot be started once stopped");
            default:
                throw new Error("Invalid WorkerState");
        }

        // Wait until the startTime is initialized by the worker.
        while (startTime == 0) {
            try {
                startTimeInitialized.await();
            } catch (InterruptedException ignore) {
                // Ignore - it will be ready very soon.
            }
        }
    }
600069
@Override
    public void run() {
        // Check for a pending exception.  A CancellationException could be set if a cancel() was driven while this Runnable
        // was being re-scheduled.
        if (this.m_pendingException != null) {
            return;
        }

        // NOTE: Already running in Default Executor thread.
        try {
            this.m_runnable.run();
        } catch (Exception e) {
            this.m_pendingException = new ExecutionException(e);
            this.m_coordinationLatch.countDown();
            return;
        }

        try {
            long scheduleTime = this.m_periodInterval;
            if (!this.m_scheduledWithDelay) {
                this.m_myNextExecutionTime = this.m_myNextExecutionTime + this.m_periodInterval;
                long currentTime = System.nanoTime();

                scheduleTime = (this.m_myNextExecutionTime > currentTime) ? (this.m_myNextExecutionTime - currentTime) : 0;
            }

            m_schedFuture = this.m_scheduledExecutor.schedule(this, scheduleTime, TimeUnit.NANOSECONDS);
        } catch (Exception e) {
            this.m_pendingException = e;
            this.m_coordinationLatch.countDown();
        }
    }
877245
public void start() {
        if(actionInBackground != null) {

            Runnable jobToRun = new Runnable() {
                @Override
                public void run() {
                    result = (JobResult) actionInBackground.doAsync();
                    onResult();
                }
            };

            if(getExecutorService() != null) {
               asyncFutureTask = (FutureTask) getExecutorService().submit(jobToRun);
            } else {
                asyncThread = new Thread(jobToRun);
                asyncThread.start();
            }
        }
    }
791533
@Override
  public void start() {
    if (mProgressiveStartActivated) {
      resetProgressiveStart(0);
    }
    if (isRunning()) return;
    if (mCallbacks != null) {
      mCallbacks.onStart();
    }
    scheduleSelf(mUpdater, SystemClock.uptimeMillis() + FRAME_DURATION);
    invalidateSelf();
  }
344358
public void start() throws Exception
    {
        Preconditions.checkState(state.compareAndSet(State.LATENT, State.STARTED), "Cannot be started more than once");

        startTask.set(AfterConnectionEstablished.execute(client, new Runnable()
                {
                    @Override
                    public void run()
                    {
                        try
                        {
                            internalStart();
                        }
                        finally
                        {
                            startTask.set(null);
                        }
                    }
                }));
    }
949072
@GwtIncompatible
    public static void start() {
        computation().start();
        io().start();
        newThread().start();
        single().start();
        trampoline().start();
        SchedulerPoolFactory.start();
    }