Find total hours between two Dates

I have two Date objects and I need to get the time difference so I can determine the total hours between them. They happen to be from the same day. The result I would like would have the hours and minutes.

When I use .toString() on my Date obje开发者_StackOverflow中文版ct I get this: Fri Dec 18 08:08:10 CST 2009

I've tried the following:

long diff = (this.endDate.getTime() - this.startDate.getTime()) / (60 * 60 * 1000);

But this only gives me hours, not the minutes. I know this is a simple problem, but I can't figure it out atm.

Edits: Final solution for those interested. Thanks to Michael Brewer-Davis

Period p = new Period(this.startDate, this.endDate);
long hours = p.getHours();
long minutes = p.getMinutes();
    
String format = String.format("%%0%dd", 2);
    
return Long.toString(hours) + ":" + String.format(format, minutes);

This should work.

long secs = (this.endDate.getTime() - this.startDate.getTime()) / 1000;
int hours = secs / 3600;    
secs = secs % 3600;
int mins = secs / 60;
secs = secs % 60;

Here's how it works with Joda time:

DateTime startTime, endTime;
Period p = new Period(startTime, endTime);
int hours = p.getHours();
int minutes = p.getMinutes();

You could format with Joda's formatters, e.g., PeriodFormat, but I'd suggest using Java's. See this question for more details.

EDIT: be careful using this method to check hours between. This function don't respect days between. It get just hours between two times. 2022-07-20 11.00 and 2022-07-21 12.00 will return 1 hour, not 25 hours.

Here's simple way:

private static int hoursDifference(Date date1, Date date2) {

    final int MILLI_TO_HOUR = 1000 * 60 * 60;
    return (int) (date1.getTime() - date2.getTime()) / MILLI_TO_HOUR;
}

java.time.Duration

I should like to contribute the modern (java 8+) answer. The solutions using Joda-Time are fine. The Joda-Time project is in maintenance mode, so for new code we should not use it. I follow the official recommendation from the Joda-Time project and use java.time, the modern Java date and time API:

    Duration dur = Duration.between(startDate, endDate);
    String result = String.format("%d:%02d", dur.toHours(), dur.toMinutesPart());
    System.out.println(result);

This works if startDate and endDate both have type Instant or OffsetDateTime or ZonedDateTime or LocalDateTime or LocalTime. All of the mentioned types are from java.time package. If starting with LocalDate, call either of the atStartOfDay methods.

The toMinutesPart methof was introduced in Java 9. If you are using Java 8 (ot ThreeTen Backport), search for java format duration or similar to learn how to format the duration into hours and minutes.

Two quotes from the Joda-Time home page:

Users are now asked to migrate to java.time (JSR-310).

Note that Joda-Time is considered to be a largely “finished” project. No major enhancements are planned. If using Java SE 8, please migrate to java.time (JSR-310).

Links

• Oracle tutorial: Date Time explaining how to use java.time.
• Joda-Time home page

Please follow Somaiah's suggestion in a comment, use Hours instead:

Hours hours = Hours.hoursBetween(startTime, endTime);

The call to getHours() will only return the hour section of the time difference and ignore all year, month differences so it would not be correct in some cases.

If you use Period.toStandardHours() to try to convert the time difference into hours the calculation will throw an exception if the time difference between the two dates includes difference in either year or month, since the length of month is unknown.

So the getTime() method, I presume, returns an integer.

In which case, the left set of parentheses has type int, right?

and

(60*60*1000)

is also an int.

Which means you get long diff = ((int)/(int)) so the integer division is done BEFORE you cast stuff to long. And hence you lose your minutes.

Try casting them BEFORE you divide.

for kotlin, you can use below function and get hours between two date

private val dateFormat: String = "yyyy-MM-dd @ hh:mm a"
val startDate = SimpleDateFormat(dateFormat).parse("2018-10-01 @ 12:33 PM")
val endDate = SimpleDateFormat(dateFormat).parse("2018-10-01 @ 02:46 PM")

private fun hoursDifference(date1: Date, date2: Date): Int {
    val milliToHour : Long = 1000 * 60 * 60
    return ((date1.time - date2.time) / milliToHour).toInt()
}

println(hoursDifference(endDate,startDate).toString())

Output: 2

Even though there's already an accepted answer, this is what worked for me using the Joda time library.

/**
 *
 * @param date1
 * @param date2
 * @return hours between two dates rounded down
 */
public static int hoursBetween(DateTime date1, DateTime date2) {
    if(date1 == null || date2 == null) return NOT_FOUND;

    return Math.abs(Hours.hoursBetween(date1.toLocalDateTime(), date2.toLocalDateTime()).getHours());
}

private void getHours(Date d1, Date d2){
long diff = d2.getTime() - d1.getTime();

  long diffSeconds = diff / 1000 % 60;
        long diffMinutes = diff / (60 * 1000) % 60;
  long diffDays = diff / (24 * 60 * 60 * 1000);
        long diffHours = diff / (60 * 60 * 1000) % 24;

        System.out.print(diffDays + " days, ");
        System.out.print(diffHours + " hours, ");
        System.out.print(diffMinutes + " minutes, ");
        System.out.print(diffSeconds + " seconds.\n");

}`

//Displays: /* 1 days, 1 hours, 1 minutes, 50 seconds. */

Here's a pure Java 8+ solution that does not involve Joda or mathematical operations

import java.time.*;
import java.time.temporal.*;

// given two java.util.Dates
Date startDate ...
Date endDate ...

// convert them to ZonedDateTime instances
ZonedDateTime start = ZonedDateTime.ofInstant(startDate.toInstant(), ZoneId.systemDefault());
ZonedDateTime end = ZonedDateTime.ofInstant(endDate.toInstant(), ZoneId.systemDefault());

// get the total duration of minutes between them
Duration total = Duration.ofMinutes(ChronoUnit.MINUTES.between(start, end));

// use the duration to determine the hours and minutes values
long hours = total.toHours();
long minutes = total.minusHours(hours).toMinutes();

Here is the simple method :- Check your Date format,if your date not in this format then change it and pass to this method it will give you a String which is your result. Modify the method as per the requirement.

private String getDateAsTime(String datePrev) {
        String daysAsTime = "";
        long day = 0, diff = 0;
        String outputPattern = "yyyy:MM:dd HH:mm:ss";
        SimpleDateFormat outputFormat = new SimpleDateFormat(outputPattern);
        Calendar c = Calendar.getInstance();
        String dateCurrent = outputFormat.format(c.getTime());
        try {
           Date  date1 = outputFormat.parse(datePrev);
            Date date2 = outputFormat.parse(dateCurrent);
            diff = date2.getTime() - date1.getTime();
            day = TimeUnit.DAYS.convert(diff, TimeUnit.MILLISECONDS);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        if (day == 0) {
            long hour = TimeUnit.HOURS.convert(diff, TimeUnit.MILLISECONDS);
            if (hour == 0)
                daysAsTime = String.valueOf(TimeUnit.MINUTES.convert(diff, TimeUnit.MILLISECONDS)).concat(" minutes ago");
            else
                daysAsTime = String.valueOf(hour).concat(" hours ago");
        } else {
            daysAsTime = String.valueOf(day).concat(" days ago");
        }
        return daysAsTime;
    }

Hope this will help,