Core Java · interview question
What happens if you override only the equals method and not hashCode in a Java class used in a HashSet?
Multiple choiceEasychapter-4-curatedpremiumcore-javaequals-and-hashcode-in-collections
Answer and explanation
Correct answer
D. HashSet may contain duplicates.
Why
HashSet uses both equals and hashCode to determine object uniqueness. Without a consistent hashCode, objects that are considered equal by equals may end up in different buckets, leading to duplicates.
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