Checking whether all tasks in ThreadPoolExecutor are completed

Question

How can I check whether all tasks submitted to ThreadPoolExecutor are completed?

New tasks can be added from previously submitted tasks, so I can't call shutdown followed by awaitTermination nor invokeAll, as it will ignore these new tasks.

Related but different problem so not quite a dupe - http://stackoverflow.com/questions/3929361/how-to-wait-for-all-tasks-in-an-threadpoolexecutor-to-finish-without-shutting-do — djechlin, May 14 '13 at 21:38

score 7 · Accepted Answer · answered May 15 '13 at 09:31

7

yourThreadPoolExecutor.getActiveCount(); will return 0 when all tasks have completed.

answered May 15 '13 at 09:31

assylias

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I have a flacky test that may be related to using this. Reading the documenttion states that this number is an aproximation: "Returns the approximate number of threads that are actively executing tasks". – borjab Oct 26 '21 at 17:54

score 1 · Answer 2 · answered May 15 '13 at 01:40

1

You can use ThreadPoolExecutor.getCompletedTaskCount()

answered May 15 '13 at 01:40

Evgeniy Dorofeev

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Checking whether all tasks in ThreadPoolExecutor are completed

2 Answers2