Collections · interview question
Which of the following statements about HashMap is true?
Multiple choiceMediumchapter-4-curatedpremiumcollectionsmap-interface-and-hashmap
Answer and explanation
Correct answer
B. HashMap allows one null key and multiple null values.
Why
HashMap allows one null key and multiple null values. It does not maintain insertion order and is not synchronized by default; if thread safety is needed, it should be externally synchronized.
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