Java · Mid-level · Theory

You need to call three external services in parallel and assemble one result from their responses. How would you do this with CompletableFuture, and what would you watch out for?

~4 min by voice

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This checks whether you can properly organize parallel asynchronous calls with CompletableFuture and whether you understand the pitfalls: thread pools, errors, timeouts, blocking and carrying context across threads.

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concurrency completablefuture

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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