I want to record the time using System.currentTimeMillis() when a user begins something in my program. When he finishes, I will subtract the current System.currentTimeMillis() from the start variable, and I want to show them the time elapsed using a human readable format such as "XX hours, XX mins, XX seconds" or even "XX mins, XX seconds" because its not likely to take someone an hour.
What's the best way to do this?
Since 1.5 there is the java.util.concurrent.TimeUnit class, use it like this:
ReplyDeleteString.format("%d min, %d sec",
TimeUnit.MILLISECONDS.toMinutes(millis),
TimeUnit.MILLISECONDS.toSeconds(millis) -
TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millis))
);
For Java versions below 1.5 or for systems that do not fully support the TimeUnit class (such as Android before API version 9), the following equations can be used:
int seconds = (int) (milliseconds / 1000) % 60 ;
int minutes = (int) ((milliseconds / (1000*60)) % 60);
int hours = (int) ((milliseconds / (1000*60*60)) % 24);
//etc...
Uhm... how many milliseconds are in a second? And in a minute? Division is not that hard.
ReplyDeleteint seconds = (int) ((milliseconds / 1000) % 60);
int minutes = (int) ((milliseconds / 1000) / 60);
Continue like that for hours, days, weeks, months, year, decades, whatever.
Either hand divisions, or use the SimpleDateFormat API.
ReplyDeletelong start = System.currentTimeMillis();
// do your work...
long elapsed = System.currentTimeMillis() - start;
DateFormat df = new SimpleDateFormat("HH 'hours', mm 'mins,' ss 'seconds'");
df.setTimeZone(TimeZone.getTimeZone("GMT+0"));
System.out.println(df.format(new Date(elapsed)));
Edit by Bombe: It has been shown in the comments that this approach only works for smaller durations (i.e. less than a day).
I would not pull in the extra dependency just for that (division is not that hard, after all), but if you are using Commons Lang anyway, there are the DurationFormatUtils.
ReplyDeleteBased on @siddhadev's answer, I wrote a function to do this recently. Just thought I'd share in case anyone finds it useful:
ReplyDelete/**
* Convert a millisecond duration to a string format
*
* @param millis A duration to convert to a string form
* @return A string of the form "X Days Y Hours Z Minutes A Seconds".
*/
public static String getDurationBreakdown(long millis)
{
if(millis < 0)
{
throw new IllegalArgumentException("Duration must be greater than zero!");
}
long days = TimeUnit.MILLISECONDS.toDays(millis);
millis -= TimeUnit.DAYS.toMillis(days);
long hours = TimeUnit.MILLISECONDS.toHours(millis);
millis -= TimeUnit.HOURS.toMillis(hours);
long minutes = TimeUnit.MILLISECONDS.toMinutes(millis);
millis -= TimeUnit.MINUTES.toMillis(minutes);
long seconds = TimeUnit.MILLISECONDS.toSeconds(millis);
StringBuilder sb = new StringBuilder(64);
sb.append(days);
sb.append(" Days ");
sb.append(hours);
sb.append(" Hours ");
sb.append(minutes);
sb.append(" Minutes ");
sb.append(seconds);
sb.append(" Seconds");
return(sb.toString());
}
Enjoy!
Just to add more info
ReplyDeleteif you want to format like: HH:mm:ss
0 <= HH <= infinite
0 <= mm < 60
0 <= ss < 60
use this:
int h = (int) ((startTimeInMillis / 1000) / 3600);
int m = (int) (((startTimeInMillis / 1000) / 60) % 60);
int s = (int) ((startTimeInMillis / 1000) % 60);
I just had this issue now and figured this out
Date Time object
ReplyDeletedivision is easy BUT does not easily display a leading zero when needed.
ReplyDelete(say : pretty print 5min08sec)
I feel like simpledateformat is better suited for that, am I wrong ?
For small times, less than an hour, I prefer:
ReplyDeletelong millis = ...
System.out.printf("%1$TM:%1$TS", millis);
// or
String str = String.format("%1$TM:%1$TS", millis);
for longer intervalls:
private static final long HOUR = TimeUnit.HOURS.toMillis(1);
...
if (millis < HOUR) {
System.out.printf("%1$TM:%1$TS%n", millis);
} else {
System.out.printf("%d:%2$TM:%2$TS%n", millis / HOUR, millis % HOUR);
}
I think the best way is:
ReplyDeleteString.format("%d min, %d sec",
TimeUnit.MILLISECONDS.toSeconds(length)/60,
TimeUnit.MILLISECONDS.toSeconds(length) % 60 );
for correct strings ("1hour, 3sec", "3 min" but not "0 hour, 0 min, 3 sec") i write this code:
ReplyDeleteint seconds = (int)(millis / 1000) % 60 ;
int minutes = (int)((millis / (1000*60)) % 60);
int hours = (int)((millis / (1000*60*60)) % 24);
int days = (int)((millis / (1000*60*60*24)) % 365);
int years = (int)(millis / 1000*60*60*24*365);
ArrayList<String> timeArray = new ArrayList<String>();
if(years > 0)
timeArray.add(String.valueOf(years) + "y");
if(days > 0)
timeArray.add(String.valueOf(days) + "d");
if(hours>0)
timeArray.add(String.valueOf(hours) + "h");
if(minutes>0)
timeArray.add(String.valueOf(minutes) + "min");
if(seconds>0)
timeArray.add(String.valueOf(seconds) + "sec");
String time = "";
for (int i = 0; i < timeArray.size(); i++)
{
time = time + timeArray.get(i);
if (i != timeArray.size() - 1)
time = time + ", ";
}
if (time == "")
time = "0 sec";
long time = 1536259;
ReplyDelete...
return (new SimpleDateFormat("mm:ss:SSS")).format(new Date(time));
==> 25:36:259