import java.util.Arrays;

public class ArrayCallback {

    public static void main(String[] args) {
        int[] myIntArray = {1, 2, 3, 4, 5};

        int sum = Arrays.stream(myIntArray)
                .map(x -> {
                    int cube = x * x * x;
                    System.out.println(cube);
                    return cube;
                })
                .reduce(0, (left, right) -> left + right); // <-- could substitute .sum() for .reduce(...) here.
        System.out.println("sum: " + sum);
    }
}