How to wait for all threads to finish, using ExecutorService?

Question

I need to execute some amount of tasks 4 at a time, something like this:

ExecutorService taskExecutor = Executors.newFixedThreadPool(4);
while(...) {
    tas         


        

Answer 1

Follow one of below approaches.

1. Iterate through all Future tasks, returned from submit on ExecutorService and check the status with blocking call get() on Future object as suggested by Kiran
2. Use invokeAll() on ExecutorService
3. CountDownLatch
4. ForkJoinPool or Executors.html#newWorkStealingPool
5. Use shutdown, awaitTermination, shutdownNow APIs of ThreadPoolExecutor in proper sequence

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