Java tutorial
import java.time.Duration; import java.time.Instant; import java.time.temporal.ChronoUnit; public class Main { public static void main(String[] args) { Instant t1 = Instant.now(); Instant t2 = Instant.now().plusSeconds(12); long nanos = Duration.between(t1, t2).toNanos(); System.out.println(nanos); Duration gap = Duration.ofSeconds(13); // 12000000000 Instant later = t1.plus(gap); System.out.println(t1); // 2014-07-02T19:55:00.956Z System.out.println(later); // 2014-07-02T19:55:13.956Z System.out.println(ChronoUnit.MILLIS.between(t1, t2)); // 12000 } }