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javasealed-classestype-safety
Java Sealed Classes: Type-Safe Polymorphism Without instanceof Chains
Sealed classes restrict inheritance. Compiler enforces exhaustive patterns. No more surprise subclasses.
J
JOptimize Team
July 19, 2026· 11 min read
Sealed classes restrict inheritance to known types. Prevents surprise subclasses. Compiler enforces exhaustive switch. No more MatchException at runtime.
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