Java Code Generation

type Person
  name: Text
  age: Integer
  admin: Boolean

public record Person(String name, long age, boolean admin) {}

union Direction
  north
  south
  east
  west

public enum Direction { NORTH, SOUTH, EAST, WEST }

union Cheese
  farmers
  cheddar
  brie: Text

public sealed interface Cheese {
    record Farmers() implements Cheese {}
    record Cheddar() implements Cheese {}
    record Brie(String value) implements Cheese {}
}

if (x instanceof Cheese.Brie b) {
    // use b.value()
} else if (x instanceof Cheese.Farmers f) {
    // ...
}

wrap Email: Text

public record Email(String value) {
    public static Email wrap(String value) { return new Email(value); }
    public String unwrap() { return this.value(); }
}

public static java.util.Optional<String> validatePerson(Person x) {
    var errors = new java.util.ArrayList<String>();
    // ... validation checks ...
    if (!errors.isEmpty()) return java.util.Optional.of(String.join("; ", errors));
    return java.util.Optional.empty();
}