Core Java · interview question
How would you explain the hidden danger in Integer quantity = null; int count = quantity; in an interview?
Multiple choiceEasychapter-7-curatedpremiumcore-javawrapper-types-and-autoboxing
Answer and explanation
Correct answer
B. Autounboxing will throw a NullPointerException at runtime.
Why
Java will try to unbox the Integer into a primitive int. If the wrapper is null, that conversion fails at runtime, which is why wrappers should be used intentionally rather than by accident.
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