Collections · interview question
Two Product objects compare equal by SKU, but their hashCode() values differ. What bug is likely in HashSet or HashMap usage?
Multiple choiceHardchapter-4-curatedpremiumcollectionsequals-and-hashcode-in-collections
Answer and explanation
Correct answer
A. Logically equal entries may appear twice or fail lookup unexpectedly
Why
If equal objects produce different hash codes, they may land in different buckets. That breaks the assumptions hash-based collections rely on and can make duplicates or missing lookups appear like mysterious collection bugs.
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