How to convert Milliseconds to “X mins, x seconds” in Java?

Question

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 Syste

Answer 1

For small times, less than an hour, I prefer:

long 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);
}