Core Java · interview question
Why is it important for hashCode to be consistent with equals when using objects as keys in a HashMap?
Multiple choiceMediumchapter-4-curatedpremiumcore-javaequals-and-hashcode-in-collections
Answer and explanation
Correct answer
B. To ensure keys can be reliably located in the map.
Why
If hashCode is not consistent with equals, a key might not be found in the map because it could be placed in a different bucket than expected. This would lead to unreliable retrieval of values, as the map relies on hashCode to locate the correct bucket and equals to confirm key equality.
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