Core Java · interview question
In a class used as a key in a HashMap, you override equals but not hashCode. What might happen?
Multiple choiceHardchapter-4-curatedpremiumcore-javaequals-and-hashcode-in-collections
Answer and explanation
Correct answer
B. Keys may not be found even if they should be equal.
Why
Without overriding hashCode, equal objects might have different hash codes, leading to them being placed in different buckets. This results in keys that cannot be found, even if logically equal.
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