Collections · interview question
What happens if you use a mutable object as a key in a HashMap and modify it after insertion?
Multiple choiceHardchapter-4-curatedpremiumcollectionsmap-interface-and-hashmap
Answer and explanation
Correct answer
C. The lookup for the key may fail.
Why
If a mutable object used as a key is modified, its hash code may change, causing lookup operations to fail because the new hash code may not match the hash bucket where it was originally stored.
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