Sealed with Records
Model closed hierarchies.
Sealed Plus Records
Sealed interfaces and records are a perfect pair. The sealed interface defines a closed set of cases; each record is one concrete, immutable case. Together they model algebraic data types.
Records Are Implicitly final
A record is automatically final, so it satisfies the rule that permitted subtypes must be final, sealed, or non-sealed. No extra modifier is needed.
All lessons in this course
- Declaring Sealed Types
- permits Clause
- Sealed with Records
- Exhaustive switch on Sealed