How to use a Timer without a delay?

Question

I know that:

Thread.sleep(1000)

means delay for exactly one second before executing the code, but it there a way to use a timer to just count the time that past when the program executes without delaying the program? Thanks.

Yes. [`System.nanoTime`](https://docs.oracle.com/javase/7/docs/api/java/lang/System.html#nanoTime()). — Boris the Spider, Apr 18 '15 at 16:44
You can use `System.currentTimeMillis()` before and after the event you want to time and subtract one from the other. — khelwood, Apr 18 '15 at 16:44

Jean-François Savard · Accepted Answer · 2015-04-18T16:52:48.560

1

Keep the current time in a variable

long oldTime = System.nanoTime();

At the end of your program, print the current time - the old time and that will be the execution time in nano seconds.

System.out.println((System.nanoTime() - oldTime));

edited Apr 18 '15 at 16:52

answered Apr 18 '15 at 16:44

Jean-François Savard

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Also, `System..currentTimeMillis()` is limited to the precision of the system clock, usually around `15ms`. `nanoTime` is always a better choice for timing events. Although, obviously any benchmark using this naive approach will be deeply flawed in any case. – Boris the Spider Apr 18 '15 at 16:51
Well, keyboard input at best is 30 ms, right? so shouldn't 15ms be more than enough? – Apr 18 '15 at 16:54
@Jean-FrançoisSavard good answer anyway. – Apr 18 '15 at 16:58

How to use a Timer without a delay?

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