Collections · interview question
If a custom object is used as an element in a HashSet, what must be correctly overridden?
Multiple choiceHardchapter-4-curatedpremiumcollectionsset-interface-and-hashset
Answer and explanation
Correct answer
C. The hashCode() and equals() methods
Why
To ensure correct behavior in a HashSet, any custom object used as an element must correctly override both the hashCode() and equals() methods. This ensures that the HashSet can accurately determine uniqueness among its elements.
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