10 methods override QueueWorkerInterface::processItem()

Cleaner::processItem in core/modules/package_manager/src/Plugin/QueueWorker/Cleaner.php
CronQueueTestDatabaseDelayException::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestDatabaseDelayException.php
CronQueueTestDeriverQueue::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestDeriverQueue.php
CronQueueTestException::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestException.php
CronQueueTestLeaseTime::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestLeaseTime.php
CronQueueTestMemoryDelayException::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestMemoryDelayException.php
CronQueueTestRequeueException::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestRequeueException.php
CronQueueTestSuspendQueue::processItem in core/modules/system/tests/modules/cron_queue_test/src/Plugin/QueueWorker/CronQueueTestSuspendQueue.php
LocaleTranslation::processItem in core/modules/locale/src/Plugin/QueueWorker/LocaleTranslation.php
The translation update functions executed here are batch operations which are also used in translation update batches. The batch functions may need to be executed multiple times to complete their task, typically this is the translation import…
ThumbnailDownloader::processItem in core/modules/media/src/Plugin/QueueWorker/ThumbnailDownloader.php
Works on a single queue item.

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