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SpringBoot JPA time stored in MySQL in local time zone

I've written a class which looks like this
#Entity
class Employee {
#Column
private String name;
#Column
private Date joinedDate;
}
Now, I assign value to joinedDate by doing new Date(). When I print this date, java will add the timezone correction to this. But Java will internally store time since epoch with no timezone. Let's say the local date was Wed Nov 29 18:43:43 IST 2017
When I store this object into database, what I expected to be stored was the time in GMT/UTC Zero timezone. (or at least, storing the number of milliseconds since epoch). But the value stored is Nov 29 18:43:43.
Which is wrong value. Because it's not storing the UTC time and it's not storing the timezone either. I expect within my application and DB dates should be stored in UTC timezone.
I would like to store UTC value while reading and writing instead of timezone where the application is running. My application could be running in different timezone but using the same database.
How can I achieve this?

I think you must use the preferred type for java 8 java.time.ZonedDateTime that can storage nanosecond precisition and timezone. Also be sure that in your database the type is TIMESTAMP.
You can check out examples in this page: enter link description here

By default java uses the machine timezone for date and calendar, if you want to change it then you have the follow options
Change JVM timezone
java -Duser.timezone=Europe/Sofia com.acme.Main
Create a date instance with a different timezone
Calendar.getInstance(TimeZone.getTimeZone("UTC")).getTime()
Use java.time api
Date convertedDatetime = Date.from(datetime.atZone(ZoneId.off("UTC").toInstant());
Obs: your observation is Right, the milliseconds since epoch have not timezone but you are using a date at the database, then it does.
Update
I found that answer , it promises to change only hibernate jdbc charset

Mongodb Epoch Date - java mapping

I would like to store dates in mongodb in epoch format (Unix time in secs or millisec, eg : "1433323417000") and have an object mapping in java java.util.Date Format (or joda.time.DateTime).
Can you let me know if this is possible ?
Thanks in advance

From MongoDb documentation :
Internally, Date objects are stored as a 64 bit integer representing the number of milliseconds since the Unix epoch (Jan 1, 1970), which results in a representable date range of about 290 millions years into the past and future.
https://docs.mongodb.org/manual/reference/method/Date/
You can find some examples on how to insert using the Java driver here
On a read, there is nothing stopping you from converting the date to any format you want.

PHP DateTime to Java Date

I have a PHP web service sending JSON responses back to my Java client. One of the fields is a DateTime value. However, I'm having problems translating the serialized PHP Date/Time to a Java Date.
For example, here is a date stored in my database:
2011-12-07 15:03:01
Here is how it's encoded in the JSON response:
1323288181
I suspected this would be the milliseconds since the Unix epoch, but when I construct a Java Date with that given value, the date turns out to be the following:
Fri Jan 16 01:34:48 CST 1970
Obviously it's not milliseconds since January 1, 1970 at midnight.
How do I go about doing this?

Looks like that's seconds since the Unix epoch - so just multiply your value by 1000 when passing it to the Date constructor.
Note that Date.toString() will always use the system time zone, but a Date really represents an instant in time, so it doesn't have a time zone.
If you're doing anything significant with dates and times, I'd thoroughly recommend using Joda Time instead of the classes in java.util.

I think it is a unixtimestamp. use this online convertor: http://www.onlineconversion.com/unix_time.htm
and here are examples how to convert it (in java):
http://www.epochconverter.com/

I am using
1970-01-01T00:00:00Z
as date time format in JSON,
then I make sure both sides parse it correctly

How to convert java.sql.Timestamp value from EST to UTC timezone

I have a java.sql.Timestamp variable in local timezone with following formatting
2011-07-21 00:40:37
I need to convert it to UTC
I asked this question to see if it can be done by mysql, but received no answers.
I guess I have to somehow do it in java code before substituting it in the query

I recommend using Joda Time to parse the timestamp. You'll need to set the timezone to EST and then get the UTC time from there. You could do the same thing with the generic Java Date, but Joda is easier to work with.

Best way to extract a timezone from a mail Date header in Java?

I need to store the timezone an email was sent from. Which is the best way to extract it from the email's 'Date:' header (an RFC822 date)? And what is the recommended format to store it in the database (I'm using hibernate)?

I recommend you use Mime4J.
The library is designed for parsing all kinds of email crap.
For parsing dates you would use its DateTimeParser.
int zone = new DateTimeParser(new StringReader("Fri, 27 Jul 2012 09:13:15 -0400")).zone();
After that I usually convert the datetimes to Joda's DateTime. Don't use SimpleDateFormatter as will not cover all the cases for RFC822.
Below will get you the Joda TimeZone (from the int zone above) which is superior to Java's TZ.
// Stupid hack in case the zone is not in [-+]zzzz format
final int hours;
final int minutes;
if (zone > 24 || zone < -24 ) {
hours = zone / 100;
minutes = minutes = Math.abs(zone % 100);
}
else {
hours = zone;
minutes = 0;
}
DateTimeZone.forOffsetHoursMinutes(hours, minutes);
Now the only issue is that the Time Zone you will get always be a numeric time zone which may still not be the correct time zone of the user sending the email (assuming the mail app sent the users TZ and not just UTC).
For example -0400 is not EDT (ie America/New_York) because it does not take Daylight savings into account.

Probably easiest to parse with JodaTime as it supports ISO8601 see Date and Time Parsing and Formatting in Java with Joda Time.
DateTimeFormatter parser2 = ISODateTimeFormat.dateTimeNoMillis();
System.out.println(parser2.parseDateTime(your_date_string));
Times must always be stored in UTC (GMT) with a timezone - i.e. after parsing convert from the timezone to GMT and remove daylight savings offset and save the original timezone.
You must store the date with the timezone after converting to UTC.
If you remove or don't handle the timezone it will cause problems when dealing with data that has come from a different timezone.

Extract the data from the header using some sort of substring or regular expression. Parse the date with a SimpleDateFormatter to create a Date object.

The timezone in the email will not show in which timezone it was send. Some programs use ever UTC or GMT. Of course the time zone is part of the date time value and must also be parse.
Why do you want know it.
- Do you want normalize the timestamp? Then use a DateFormat for parsing it.
- Do you want detect the timezome of the user that send the email? This will not correctly work.

It looks like you already mentioned this in one of your comments, but I think it's your best answer. The JavaMail library contains RFC822 Date header parsing code in javax.mail.internet.MailDateFormat. Unfortunately it doesn't expose the TimeZone parsing directly, so you will need to copy the necessary code directly from javax.mail.internet.MailDateParser, but it's worth taking advantage of the careful work already done.
As for storing it, the parser will give you the date as an offset, so you should be able to store it just fine as an int (letting Hibernate translate that to your database for you).