Calculate process elapsed time
public class Main { public static void main(String[] args) { long start = System.nanoTime(); System.out.println("Start: " + start); for (int i = 0; i < 100; i++) { for (int j = 0; j < 100; j++) { System.out.println("asdf"); } } long end = System.nanoTime(); System.out.println("End : " + end); long elapsedTime = end - start; System.out.println(elapsedTime + " nano seconds"); } }