How to calculate “time ago” in Java?

Question

In Ruby on Rails, there is a feature that allows you to take any Date and print out how "long ago" it was.

For example:

8 minutes ago
8 hours ago
8 days ago
8 months ago
8 years ago

Is there an easy way to do this in Java?

Answer 1

java.time

Using the java.time framework built into Java 8 and later.

LocalDateTime t1 = LocalDateTime.of(2015, 1, 1, 0, 0, 0);
LocalDateTime t2 = LocalDateTime.now();
Period period = Period.between(t1.toLocalDate(), t2.toLocalDate());
Duration duration = Duration.between(t1, t2);

System.out.println("First January 2015 is " + period.getYears() + " years ago");
System.out.println("First January 2015 is " + period.getMonths() + " months ago");
System.out.println("First January 2015 is " + period.getDays() + " days ago");
System.out.println("First January 2015 is " + duration.toHours() + " hours ago");
System.out.println("First January 2015 is " + duration.toMinutes() + " minutes ago");

Answer 2

Have you considered the TimeUnit enum? It can be pretty useful for this kind of thing

    try {
        SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy");
        Date past = format.parse("01/10/2010");
        Date now = new Date();

        System.out.println(TimeUnit.MILLISECONDS.toMillis(now.getTime() - past.getTime()) + " milliseconds ago");
        System.out.println(TimeUnit.MILLISECONDS.toMinutes(now.getTime() - past.getTime()) + " minutes ago");
        System.out.println(TimeUnit.MILLISECONDS.toHours(now.getTime() - past.getTime()) + " hours ago");
        System.out.println(TimeUnit.MILLISECONDS.toDays(now.getTime() - past.getTime()) + " days ago");
    }
    catch (Exception j){
        j.printStackTrace();
    }

Answer 3

Take a look at the PrettyTime library.

It's quite simple to use:

import org.ocpsoft.prettytime.PrettyTime;

PrettyTime p = new PrettyTime();
System.out.println(p.format(new Date()));
// prints "moments ago"

You can also pass in a locale for internationalized messages:

PrettyTime p = new PrettyTime(new Locale("fr"));
System.out.println(p.format(new Date()));
// prints "à l'instant"

As noted in the comments, Android has this functionality built into the android.text.format.DateUtils class.

Answer 4

Here is my Java Implementation of this

    public static String relativeDate(Date date){
    Date now=new Date();
    if(date.before(now)){
    int days_passed=(int) TimeUnit.MILLISECONDS.toDays(now.getTime() - date.getTime());
    if(days_passed>1)return days_passed+" days ago";
    else{
        int hours_passed=(int) TimeUnit.MILLISECONDS.toHours(now.getTime() - date.getTime());
        if(hours_passed>1)return days_passed+" hours ago";
        else{
            int minutes_passed=(int) TimeUnit.MILLISECONDS.toMinutes(now.getTime() - date.getTime());
            if(minutes_passed>1)return minutes_passed+" minutes ago";
            else{
                int seconds_passed=(int) TimeUnit.MILLISECONDS.toSeconds(now.getTime() - date.getTime());
                return seconds_passed +" seconds ago";
            }
        }
    }

    }
    else
    {
        return new SimpleDateFormat("HH:mm:ss MM/dd/yyyy").format(date).toString();
    }
  }

Answer 5

  public class TimeUtils {

      public final static long ONE_SECOND = 1000;
      public final static long SECONDS = 60;

      public final static long ONE_MINUTE = ONE_SECOND * 60;
      public final static long MINUTES = 60;

      public final static long ONE_HOUR = ONE_MINUTE * 60;
      public final static long HOURS = 24;

      public final static long ONE_DAY = ONE_HOUR * 24;

      private TimeUtils() {
      }

      /**
       * converts time (in milliseconds) to human-readable format
       *  "<w> days, <x> hours, <y> minutes and (z) seconds"
       */
      public static String millisToLongDHMS(long duration) {
        StringBuffer res = new StringBuffer();
        long temp = 0;
        if (duration >= ONE_SECOND) {
          temp = duration / ONE_DAY;
          if (temp > 0) {
            duration -= temp * ONE_DAY;
            res.append(temp).append(" day").append(temp > 1 ? "s" : "")
               .append(duration >= ONE_MINUTE ? ", " : "");
          }

          temp = duration / ONE_HOUR;
          if (temp > 0) {
            duration -= temp * ONE_HOUR;
            res.append(temp).append(" hour").append(temp > 1 ? "s" : "")
               .append(duration >= ONE_MINUTE ? ", " : "");
          }

          temp = duration / ONE_MINUTE;
          if (temp > 0) {
            duration -= temp * ONE_MINUTE;
            res.append(temp).append(" minute").append(temp > 1 ? "s" : "");
          }

          if (!res.toString().equals("") && duration >= ONE_SECOND) {
            res.append(" and ");
          }

          temp = duration / ONE_SECOND;
          if (temp > 0) {
            res.append(temp).append(" second").append(temp > 1 ? "s" : "");
          }
          return res.toString();
        } else {
          return "0 second";
        }
      }


      public static void main(String args[]) {
        System.out.println(millisToLongDHMS(123));
        System.out.println(millisToLongDHMS((5 * ONE_SECOND) + 123));
        System.out.println(millisToLongDHMS(ONE_DAY + ONE_HOUR));
        System.out.println(millisToLongDHMS(ONE_DAY + 2 * ONE_SECOND));
        System.out.println(millisToLongDHMS(ONE_DAY + ONE_HOUR + (2 * ONE_MINUTE)));
        System.out.println(millisToLongDHMS((4 * ONE_DAY) + (3 * ONE_HOUR)
            + (2 * ONE_MINUTE) + ONE_SECOND));
        System.out.println(millisToLongDHMS((5 * ONE_DAY) + (4 * ONE_HOUR)
            + ONE_MINUTE + (23 * ONE_SECOND) + 123));
        System.out.println(millisToLongDHMS(42 * ONE_DAY));
        /*
          output :
                0 second
                5 seconds
                1 day, 1 hour
                1 day and 2 seconds
                1 day, 1 hour, 2 minutes
                4 days, 3 hours, 2 minutes and 1 second
                5 days, 4 hours, 1 minute and 23 seconds
                42 days
         */
    }
}

more @Format a duration in milliseconds into a human-readable format

Answer 6

After long research i found this.

    public class GetTimeLapse {
    public static String getlongtoago(long createdAt) {
        DateFormat userDateFormat = new SimpleDateFormat("E MMM dd HH:mm:ss Z yyyy");
        DateFormat dateFormatNeeded = new SimpleDateFormat("MM/dd/yyyy HH:MM:SS");
        Date date = null;
        date = new Date(createdAt);
        String crdate1 = dateFormatNeeded.format(date);

        // Date Calculation
        DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
        crdate1 = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss").format(date);

        // get current date time with Calendar()
        Calendar cal = Calendar.getInstance();
        String currenttime = dateFormat.format(cal.getTime());

        Date CreatedAt = null;
        Date current = null;
        try {
            CreatedAt = dateFormat.parse(crdate1);
            current = dateFormat.parse(currenttime);
        } catch (java.text.ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        // Get msec from each, and subtract.
        long diff = current.getTime() - CreatedAt.getTime();
        long diffSeconds = diff / 1000;
        long diffMinutes = diff / (60 * 1000) % 60;
        long diffHours = diff / (60 * 60 * 1000) % 24;
        long diffDays = diff / (24 * 60 * 60 * 1000);

        String time = null;
        if (diffDays > 0) {
            if (diffDays == 1) {
                time = diffDays + "day ago ";
            } else {
                time = diffDays + "days ago ";
            }
        } else {
            if (diffHours > 0) {
                if (diffHours == 1) {
                    time = diffHours + "hr ago";
                } else {
                    time = diffHours + "hrs ago";
                }
            } else {
                if (diffMinutes > 0) {
                    if (diffMinutes == 1) {
                        time = diffMinutes + "min ago";
                    } else {
                        time = diffMinutes + "mins ago";
                    }
                } else {
                    if (diffSeconds > 0) {
                        time = diffSeconds + "secs ago";
                    }
                }

            }

        }
        return time;
    }
}