❓ Объясните различия между ConcurrentHashMap и HashMap?HashMap не является потокобезопасной структурой

Библиотека собеса по Java | вопросы с собеседований

❓ Объясните различия между ConcurrentHashMap и HashMap?

HashMap не является потокобезопасной структурой, и её использование в многопоточной среде может привести к непредсказуемым результатам.

ConcurrentHashMap же специально спроектирован для безопасного параллельного доступа. Он делит структуру на сегменты или ячейки и использует блокировки только на части данных, обеспечивая высокую степень параллелизма.

С версии Java 8 применяется CAS-логика и синхронизация на уровне bin-ов для модификаций, а чтения выполняются без блокировок.

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Create: 2025-05-23
Last Update: 2025-06-10 20:24:17

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