var in lambda parameters

Definition

Java 11 lets you write var for lambda parameters. It does not change behaviour, but it lets you add annotations such as @NonNull to a parameter without writing out its type.

Example code

Using var for lambda parameters

import java.util.List;
import java.util.function.BiFunction;

class Demo {
    public static void main(String[] args) {
        BiFunction<Integer, Integer, Integer> add = (var a, var b) -> a + b;
        System.out.println(add.apply(2, 3));

        List<String> names = List.of("asha", "ravi");
        names.forEach((var name) -> System.out.println(name.toUpperCase()));
    }
}

// Output:
// 5
// ASHA
// RAVI