Java · Mid-level · Theory

One thread sets a stop flag, and a worker thread checks that flag in a loop, but sometimes the worker never stops. Why does that happen and how do you fix it?

~4 min by voice

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This checks understanding of the Java Memory Model: why a write by one thread may not be visible to another without synchronization, how volatile provides visibility through happens-before, what it is not (atomicity), and whether the candidate knows the standard way to stop threads with interrupt.

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memory model concurrency

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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