如何通过Java8的Instant去统计程序执行时间?？

代码如下所示

import java.time.Duration;
import java.time.Instant;
import java.util.concurrent.TimeUnit;

public class DurationDemo {

    public static void main(String[] args) throws InterruptedException {
        //开始时间
        Instant stime = java.time.Instant.now();
        //程序执行过程
        TimeUnit.SECONDS.sleep(2);
        //结束时间
        Instant etime = java.time.Instant.now();
        //统计时间_毫秒
        System.out.println(Duration.between(stime, etime).toMillis());
        //统计时间 _秒
        System.out.println(Duration.between(stime, etime).getSeconds());
        //统计时间_分钟
        System.out.println(Duration.between(stime, etime).toMinutes());
    }
}