計算消逝時間

Question

該程序將向用戶顯示程序的開始時間，結束時間和流逝時間。例如，如果程序在09:23:45開始並在09:23:55結束，則對用戶的輸出將如此，開始時間：09h：23m：45s結束時間：09h：23m：55s經過時間00h ：00米：10秒。我有問題，會顯示時間... 請幫助

這是主要的

import java.util.concurrent.TimeUnit; 
import java.text.SimpleDateFormat; 
public class ElapsedTimeWatch { 

public static void main(String... args) throws InterruptedException { 

    TimeWatch watch = TimeWatch.start(); 
    SimpleDateFormat dateFormat = new SimpleDateFormat("HH'h':mm'm':ss's'"); 
    System.out.println("Start Time is : " + dateFormat.format(timestart)); 
    String.format("%02dh:%02dm:%02ds", 
        TimeUnit.MILLISECONDS.toHours(watch.timestart()),//dateFormat.format(start) 
        TimeUnit.MILLISECONDS.toSeconds(watch.timestart()) - 
          TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(watch.timestart()))); 









    Thread.sleep(1000 * 10); 



    System.out.println("End Time is : " + dateFormat.format(timeend)); 
    String.format("%02dh:%02dm:%02ds", 
        TimeUnit.MILLISECONDS.toHours(watch.timeend()), 
        TimeUnit.MILLISECONDS.toSeconds(watch.timeend()) - 
          TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(watch.timeend()))); 









    System.out.println("Elapsed Time custom format: " + watch.toMinuteSeconds()); 



} 
} 

時手錶類

import java.util.concurrent.TimeUnit; 

public class TimeWatch { 

long starts; 



private TimeWatch() { 
    reset(); 
} 

public static TimeWatch start() { 
    return new TimeWatch(); 
} 

public TimeWatch reset() { 
    starts = System.currentTimeMillis(); 
    return this; 
} 




public long time() { 
    long ends = System.currentTimeMillis(); 
    return ends - starts; 
} 

//Start Time 
public long timestart() { 
    starts = System.currentTimeMillis(); 
    return starts; 
} 
//End Time 
public long timeend() { 
    long ends = System.currentTimeMillis(); 
    return ends; 
} 





public long time(TimeUnit unit) { 
    return unit.convert(time(), TimeUnit.MILLISECONDS); 


public String toMinuteSeconds(){ 
    return String.format("%d min, %d sec", time(TimeUnit.MINUTES), 
      time(TimeUnit.SECONDS) - time(TimeUnit.MINUTES)); 
} 




} 

Answer 1

由於根據oracle documentation，System.nanoTime（）與時鐘無關。所以，在這種情況下，我們可以使用System.currentTimeMillis();來啓動定時器。一旦計時器停止，我們可以使用下面的代碼打印失效：

public static void main(String[] args) throws InterruptedException { 
    long start = System.currentTimeMillis(); 
    SimpleDateFormat dateFormat = new SimpleDateFormat("HH'h':mm'm':ss's'"); 
    Thread.sleep(10000); 
    long end = System.currentTimeMillis(); 
    long difference = end - start; 
    System.out.println("Start :" + dateFormat.format(start)); 
    System.out.println("End :" + dateFormat.format(end)); 
    String format = String.format("%d min, %d sec", 
      TimeUnit.MILLISECONDS.toMinutes(difference), 
      TimeUnit.MILLISECONDS.toSeconds(difference) - 
      TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(difference)) 
     ); 
    System.out.println(format); 
}