Java - usando arreglos y métodos con Función

import java.util.Arrays;

public class MyClass {

    public static void main(String args[]) {

      System.out.println(Arrays.toString(createEvenArray(20)));

      System.out.println(sumArray(createEvenArray(20)));

    }

    public static int[] createEvenArray(int n){

        int[] result = new int[n];

        for(int i = 1; i <= n; ++i){

            result[i-1] = i*2;

        }

        return result;

    }

    public static int sumArray(int[] arr){

        int sum = 0;

        for(int i = 0; i < arr.length; ++i){

            sum += arr[i];

        }

        return sum;

    }

}