🎬 Local Record Classes
(with a “French actors” theme 🇫🇷🎬)
A local record class is like a local class, except it’s a record declared inside a method body.
Why it’s useful:
In stream pipelines you often need a small, temporary “carrier” type for intermediate results (e.g., actor + total earnings). A local record keeps the code readable and strongly typed, without introducing extra top-level classes.Example: Top actors by earnings for a given month
We model:
- an actor (Actor)
- a payment for a shooting date (Pay)
- and inside findTopActors(...) we declare a local record ActorIncome to make stream operations clearer.
Key point: local records are implicitly static
Just like nested records, a local record is implicitly static.
That means:
- methods inside the local record cannot capture variables from the enclosing method,
- unlike regular local classes (non-record), which can capture effectively final local variables.
In short: local records are great for clean, temporary data holders—but they don’t close over method locals.