Concurrency basics · interview question

When using a ConcurrentHashMap, what happens if you attempt to insert a null value?

Multiple choiceMediumchapter-15-curatedpremiumconcurrencyconcurrent-collections

The map accepts the null value.The operation is silently ignored.The map throws a NullPointerException.The null is converted to a default value.

Answer and explanation

Correct answer

C. The map throws a NullPointerException.

ConcurrentHashMap does not allow null keys or values and will throw a NullPointerException if you attempt to insert a null value.

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