final Boolean running = system.getThumbnailGenerationRunning();
if (((running == null) || !running.booleanValue())) {
if (this.thumbnailCreator != null) {
this.thumbnailCreator.interrupt();
}
this.thumbnailCreator = new ThumbnailCreationThread(system);
this.thumbnailCreator.start();
} else {
logger.info("skipped create-thumbnails, already running");
}
}