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Java / Map and its implementations

Difference between remove() and clear() methods in HashMap.

Map stores key/value pairs. HashMap is unordered; LinkedHashMap keeps insertion order; TreeMap sorts keys; ConcurrentHashMap is safe for concurrent writes.

We can remove entries from HashMap using remove(key) or clear() methods. remove method removes the mapping for the key specified in the parameter while clear() method removes all the entries from the HashMap and returns void.

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