How to get the time difference of different timezone?

Question

I am trying to get the difference between the current time and the time which is stored in DB. I tried below code but its not giving the correct result since java.lang.System.currentTimeMillis() returns UTC time whereas we save date to our application in EST format.

Code :

java.lang.System.currentTimeMillis() - emp.getModifiedDate()

Could you please suggest me a correct way to do it ?It will be very helpful for me

Thanks

`System.currentTimeMillis()` actually returns the *System* time, not the UTC time. — Okx, Jun 20 '17 at 10:01
If you're storing the milliseconds in the database, they're not in a timezone. It's just the number of milliseconds since Unix epoch (or some other epoch). — Andy Turner, Jun 20 '17 at 10:02
@AndyTurner Thanks for you response. I am storing date time in the DB, not millisecond — Rahman, Jun 20 '17 at 10:05
Ok, so when in the day are you trying to calculate the time? Start of day? Noon? Current time? — Andy Turner, Jun 20 '17 at 10:08
I want to get the difference between the date saved in DB and current time — Rahman, Jun 20 '17 at 10:09
A suggestion could be to pay attention too at what java version you are using , in java 7 and previous you can use **Calendar** , from java 8 **java.time.ZoneId** — Frank, Jun 20 '17 at 10:53

score 0 · Answer 1 · answered Jun 20 '17 at 10:10

System.currentTimeMillis() returns the number of milliseconds since January 1, 1970 UTC. It is time-zone agnostic.

If you are storing the time in the database as millis then simply subtracting the two numbers will give you the correct difference.

If you are storing the time in some other way (e.g. as a String), you can parse it (e.g. with SimpleDateFormat) to take into account the time zone and then obtain a Date from which you can obtain the millis.

score 0 · Answer 2 · answered Jun 20 '17 at 10:17

0

Hope this helps! This will give you difference in no of days.

Date date1 = new Date();   
long diff = date1.getTime() - emp.getModifiedDate().getTime();           
System.out.println((int) (diff) / (1000 * 60 * 60 * 24)));

For more read this

answered Jun 20 '17 at 10:17

Rajat Khandelwal

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How to get the time difference of different timezone?

2 Answers2