Concurrency basics · interview question

How would you explain the expected behavior when multiple threads attempt to update the same key in a ConcurrentHashMap in an interview?

Multiple choiceMediumchapter-15-curatedpremiumconcurrencyconcurrent-collections

Only one thread will succeed, and others will be blocked.All threads will update the key simultaneously.The updates are managed using CAS operations to ensure thread safety.The map will throw a ConcurrentModificationException.

Answer and explanation

Correct answer

C. The updates are managed using CAS operations to ensure thread safety.

Why

ConcurrentHashMap uses Compare-And-Swap (CAS) operations to ensure that concurrent updates to the same key are handled safely and atomically.

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How would you explain the expected behavior when multiple threads attempt to update the same key in a ConcurrentHashMap in an interview?

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