测量java或android中while循环中每次迭代所花费的时间

Question

我想知道在while循环中执行迭代花了多长时间？更确切地说，我编写了一个while循环来执行下载任务并将数据写入文件，我想在每次循环进入下一次迭代时测量下载速度。

Answer 1

只需使用calendar.getInstance（）。getTimeInMillis（）;

List <Long> elapsedTimes = new ArrayList<>();   //contains the time taken for all iterations.
long startTime = Calendar.getInstance().getTimeInMillis();
long elapsedTime = startTime;
for (... your for loop)
{ 
    ... //do your stuff ...
    long currTime = Calendar.getInstance.getTimeInMillis();
    elapsedTimes.add(currTime - elapsedTime);
    elapsedtime = currTime;

}
long endTime = Calendar.getInstance().getTimeInMillis();

long totalTime= endtime - startTime.