Core Java · interview question
Consider a HashMap storing product names as keys and their prices as values. What potential issue should you consider when using mutable objects as keys?
Multiple choiceHardchapter-4-curatedpremiumcore-javacode-reading-with-collections
Answer and explanation
Correct answer
D. Keys might not be found if they are mutated after insertion.
Why
If a key's state changes after being added to the HashMap, its hash code might change, leading to retrieval failure since the object cannot be located in the bucket where it was originally placed.
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