Language Upgrades · interview question
What happens if a subclass of a sealed class is not declared as final, sealed, or non-sealed?
Multiple choiceHardchapter-12-curatedpremiumlanguage-upgradessealed-classes
Answer and explanation
Correct answer
D. The Java compiler will generate an error.
Why
If a subclass of a sealed class is not explicitly marked as final, sealed, or non-sealed, the Java compiler will generate an error. This ensures that all subclasses conform to the rules of the sealed hierarchy, maintaining control over the inheritance.
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