如何使用TimeUnit枚举将纳秒转换为秒？ [英] How to convert nanoseconds to seconds using the TimeUnit enum?

问题描述

如何将值从纳秒转换为秒？

How to convert a value from nanoseconds to seconds?

以下是代码段：

import java.io.*;
import java.util.concurrent.*; 
..

class Stamper { 

public static void main (String[] args) { 
long start = System.nanoTime(); 
//some try with nested loops 
long end = System.nanoTime(); 
long elapsedTime = end - start;

System.out.println("elapsed: " + elapsedTime + "nano seconds\n");

//convert to seconds 
TimeUnit seconds = new TimeUnit(); 
System.out.println("which is " + seconds.toSeconds(elapsedTime) + " seconds"); 
}}

错误是

Stamper.java:16:  enum types may not be instantiated.

这是什么意思？

推荐答案

嗯，你可以除以1,000,000,000：

Well, you could just divide by 1,000,000,000:

long elapsedTime = end - start;
double seconds = (double)elapsedTime / 1_000_000_000.0;

如果您使用 TimeUnit 进行转换，会得到你的结果很长，所以你将失去小数精度，但保持整数精度。

If you use TimeUnit to convert, you'll get your result as a long, so you'll lose decimal precision but maintain whole number precision.

这篇关于如何使用TimeUnit枚举将纳秒转换为秒？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！