Java · Mid-level · Theory

You need to configure a thread pool to process incoming tasks in a service. Which ThreadPoolExecutor parameters would you set, and why isn't Executors.newFixedThreadPool always a good fit?

~4 min by voice

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They're checking whether you understand how ThreadPoolExecutor actually works (the order core -> queue -> max -> reject) and whether you see the risk of the unbounded queue in the Executors factory methods. Plus, whether you can bring a pool to production quality: size for the type of load, rejection, names, monitoring, clean shutdown.

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concurrency executors

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The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min