UTC Timestamp + Joda Time

Question

I am trying to get the UTC TimeStamp in a simple Java program using Joda:

public Timestamp getCurrentUTC(LocalDateTime date, DateTimeZone srcTZ, DateTimeZone dstTZ, Locale l) {
    DateTime srcDateTime = date.toDateTime(srcTZ);
    DateTime dstDateTime = srcDateTime.toDateTime(dstTZ);
    
    System.out.println("UTC Time:" + dstDateTime.getMillis());      
    System.out.println("UTC Time:" + new Timestamp(dstDateTime.getMillis()));
    
    return new Timestamp(dstDateTime.getMillis());
}

The output of the program is as follows:

UTC Time:1378265162047
UTC Time:2013-09-03 23:26:02.047

The millisecond value is the correct UTC time (i.e. confirmed with GMT-4 timezone) The second value is the EST timezone.

What I need is the UTC value unchanged as java.sql.Timestamp (ie TZ independent), for a database write. Is this possible?

Edit 1

DateTime srcDateTime = date.toDateTime(srcTZ);

DateTime dstDateTime = srcDateTime.toDateTime(dstTZ);

System.out.println("UTC Time:" + dstDateTime.getMillis());

I know that srcDateTime is the local date (GMT-4), and dstDateTime is UTC (GMT-0). Output values of the dates are as follows:

Source Date:2013-09-04T09:10:43.683-04:00

Destination Date: 2013-09-04T13:10:43.683Z

I tried all the combinations to try to get the UTC value of dstDateTime as a java.sql.TimeStamp:

System.out.println("UTC Time:" + dstDateTime.getMillis());
    
System.out.println("UTC Time:" + new Timestamp(srcDateTime.toDateTime(DateTimeZone.UTC).getMillis()));

System.out.println("UTC Time:" + new Timestamp(dstDateTime.toDateTime(DateTimeZone.UTC).getMillis()));

The print output for testing:

UTC Time:1378298760226 - Correct UTC

UTC Time:2013-09-04 08:46:00.226 - Incorrect Local Date Time instead of the Expected UTC

UTC Time:2013-09-04 08:46:00.226 - Incorrect Local Date Time instead of the Expected UTC

The first print line is the correct UTC timestamp. All I need is that same value as type java.sql.TimeStamp. Anything I tried always returned the local date time of the machine.

Edit 2

I tried the following:

System.out.println("UTC Timestamp:" + date.toDateTime(srcTZ).getMillis());
System.out.println("UTC Timestamp:" + new Timestamp(date.toDateTime(srcTZ).getMillis()));

The output is as follows:

UTC Time:1378342856315 - Correct UTC Time
UTC Timestap:2013-09-04 21:00:56.315 - Local Time other than the expected UTC Time

Whenever I try to convert to TimeStamp, I loose the valid UTC value that I am after.

In terms of the method's parameters:

srcTZ = DateTimeZone.forTimeZone(TimeZone.getTimeZone("America/Montreal")
dstTZ = DateTimeZone.forTimeZone(TimeZone.getTimeZone("Etc/UTC"))
Local l = new Locale("en", "CA")

Any help is greatly appreciated.

Nick.

Edit 3

Hello Matt,

Thank you so much for your response. We are getting the same results as you. Did not know the thing about printing etc.. More specifically:

System.out.println("UTC Timestamp:" + srcDateTime.toDateTime(dstTZ).getMillis());
System.out.println("UTC Timestamp:" + srcDateTime.toDateTime(dstTZ));
System.out.println("UTC Timestamp:" + new Timestamp(srcDateTime.toDateTime(dstTZ).getMillis()));

Yields The Output:

UTC Timestamp:1378389098468 - Correct UTC Timestap (Thu, 05 Sep 2013 13:51:38 GMT)
UTC Timestamp:2013-09-05T13:51:38.468Z - Correct UTC Time
UTC Timestamp:2013-09-05 09:51:38.468 - Local time is printed, UTC is expected

The problem was brought to my attention when we realized that the DB was storing the local time instead of UTC:

+---------------------+
| effectivedate       |
+---------------------+
| 2013-09-05 09:34:11 |
+---------------------+

The Mysql timezone is set to '-00:00'

mysql> SELECT CURRENT_TIMESTAMP;
+---------------------+
| CURRENT_TIMESTAMP   |
+---------------------+
| 2013-09-05 13:48:09 |
+---------------------+

Debugging the application using eclipse debugger we realized that the local date time (2013-09-05 09:51:38.468) was being passed to the DB (Can't post images, not enough points...). The datatype is straight TimeStamp, with no string manipulation. Maybe the eclipse debugger is using String.println() function as well, not sure..

I really appreciate all the help debugging our application. Did not want to take up so much time (no pun intended) and effort...

Kind Regards,

Nick.

Answer 1

I hope this saves someone 3 days of bullshit. Set the default timezone somewhere logical in your code. Makes things more portable that having to set an env variable etc.. You can do this by adding the following somewhere logical to your code, Constructor etc..:

DateTimeZone.setDefault(DateTimeZone.UTC);

You can print UTC, concatenate UTC whatever...

Answer 2

Try this short program, it should illustrate what is going on:

LocalDateTime date = LocalDateTime.now();
DateTimeZone tz = DateTimeZone.getDefault();

System.out.println(date);
System.out.println(tz);
System.out.println("-----");
System.out.println(date.toDateTime(tz));
System.out.println(date.toDateTime(tz).toInstant());
System.out.println(date.toDateTime(tz).toDateTime(DateTimeZone.UTC));
System.out.println("-----");
System.out.println(date.toDateTime(tz).getMillis());
System.out.println(date.toDateTime(tz).toInstant().getMillis());
System.out.println(date.toDateTime(tz).toDateTime(DateTimeZone.UTC).getMillis());
System.out.println("-----");
System.out.println(new Timestamp(date.toDateTime(tz).getMillis()));
System.out.println(new Timestamp(date.toDateTime(tz).toInstant().getMillis()));
System.out.println(new Timestamp(date.toDateTime(tz).toDateTime(DateTimeZone.UTC).getMillis()));

On my computer, it outputs:

2013-09-04T19:08:35.111
America/Phoenix
-----
2013-09-04T19:08:35.111-07:00
2013-09-05T02:08:35.111Z
2013-09-05T02:08:35.111Z
-----
1378346915111
1378346915111
1378346915111
-----
2013-09-04 19:08:35.111
2013-09-04 19:08:35.111
2013-09-04 19:08:35.111

As you can see, you can get to the UTC time with either .toInstant(), or with .toDateTime(DateTimeZone.UTC). But even if you call neither of these, you will still get the UTC value when you call getMillis().

So the problem isn't with JodaTime. The problem is in how you are evaluating your results.

When you create a java.sql.Timestamp, you're passing in the milliseconds from 1/1/1970 UTC. It's only when you display it that it is applying the local time zone to the result.

Assuming you are passing it to a database as a Timestamp and not doing some interm string representation, then you should be fine. Just because it looks like the local time when you call System.out.println, doesn't mean that it is a local time internally.

The java.sql.Timestamp class extends java.util.Date - which is where it gets this behavior from.

Answer 3

I struggled with this for hours and finally found a solution.

I'm using PlayFramework - not sure if this will help anyone, but for my database connection setting I had to use:

db.default.url="jdbc:mysql://localhost/continuum?characterEncoding=UTF-8&serverTimezone=UTC"

(add the '&serverTimezone=UTC')