Android Java : How to subtract two times?

user_365860 0
Viewed 40015

I use some kind of stopwatch in my project and I have 

start time ex: 18:40:10 h
stop time  ex: 19:05:15 h

I need a result from those two values like final time = stop - start

I found some examples but they all are very confusing .

Is there any simple solution ?

subtraction timer android java
5 Answers

I am providing the modern answer.

java.time and ThreeTenABP

    DateTimeFormatter timeFormatter = DateTimeFormatter.ofPattern("H:mm:ss 'h'");

    String startTimeString = "18:40:10 h";
    String stopTimeString = "19:05:15 h";

    LocalTime startTime = LocalTime.parse(startTimeString, timeFormatter);
    LocalTime stopTime = LocalTime.parse(stopTimeString, timeFormatter);

    if (stopTime.isBefore(startTime)) {
        System.out.println("Stop time must not be before start time");
    } else {
        Duration difference = Duration.between(startTime, stopTime);

        long hours = difference.toHours();
        difference = difference.minusHours(hours);
        long minutes = difference.toMinutes();
        difference = difference.minusMinutes(minutes);
        long seconds = difference.getSeconds();

        System.out.format("%d hours %d minutes %d seconds%n", hours, minutes, seconds);
    }

Output from this example is:

0 hours 25 minutes 5 seconds

The other answers were good answers in 2010. Today avoid the classes DateFormat, SimpleDateFormat and Date. java.time, the modern Java date and time API, is so much nicer to work with.

But doesn’t it require API level 26?

No, using java.time works nicely on older and newer Android devices. It just requires at least Java 6.

  • In Java 8 and later and on newer Android devices (from API level 26) the modern API comes built-in.
  • In non-Android Java 6 and 7 get the ThreeTen Backport, the backport of the modern classes (ThreeTen for JSR 310; see the links at the bottom).
  • On (older) Android use the Android edition of ThreeTen Backport. It’s called ThreeTenABP. And make sure you import the date and time classes from org.threeten.bp with subpackages.

Links

user_57728820

Try this answer it will help you a lot

from here

In this answer, you will find subtract to two times discarding the day and month and year.

it gives you the number of minutes you will spend until you reach the second Time value.

user_81931990

Today, with newer Java (no idea, at what Android version this works):

Instant before = Instant.now();
// do stuff

Duration.between(before, Instant.now()).getSeconds()

The clumsy java ways from olden days are now gone.

user_81982030
Related