Language Upgrades · interview question
Which of the following statements about sealed classes is true?
Multiple choiceMediumchapter-12-curatedpremiumlanguage-upgradessealed-classes
Answer and explanation
Correct answer
D. A sealed class must be final if it has no subclasses.
Why
If a sealed class does not have any subclasses, it must be declared as final to indicate that it cannot be extended. This is part of maintaining a controlled class hierarchy.
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