Collections · interview question
What will happen if you try to insert a null key into a HashMap?
Multiple choiceMediumchapter-4-curatedpremiumcollectionsmap-interface-and-hashmap
Answer and explanation
Correct answer
A. The null key will be inserted successfully.
Why
HashMap allows one null key and any number of null values. Therefore, inserting a null key will succeed unless the map implementation specifically restricts it.
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