Explain the internal workings of a HashMap in Java 8.

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Accepted Answer

A hashmap uses key-value pairs for efficient data retrieval, leveraging hashing for quick access and storage.

Hashing: Converts keys into hash codes, which determine the index in an array.
Collision Handling: Techniques like chaining (linked lists) or open addressing resolve hash collisions.
Load Factor: A measure of how full the hashmap is, affecting performance; typically triggers resizing when exceeded.
Resizing: When the load factor exceeds a threshold, the hashmap doubles its size and rehashes existing entries.
Example: In a hashmap, the key 'apple' might hash to index 3, storing the value 'fruit' at that index.

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