How can we convert Timestamp datatype in Java to UTC timezone in JPA entity Java?

Question

We are using PO class to represent the sql DB and using Java JPA entity.In that class, we have one column as a field currentTime with Timestamp datatype and @version annotation from JPA.

@Version
private Timestamp currentTime;

whenever the entity gets updated, currentTime is updated with the latest time.

currentTime = new Timestamp(0); //this will create the new timestamp with current time.

but it’s currently taking the time from the server. I want to convert this time to UTC format before saving it to DB.

Anyone can help how can I convert the time to UTC time?

Java's Timestamp is UTC by default, isn't it? – Mick Jan 17 '20 at 09:21 — Mick, Jan 17 '20 at 09:21
No, its taking the server time by default – sherin shaf Jan 17 '20 at 10:26 — sherin shaf, Jan 17 '20 at 10:26

score 1 · Answer 1 · answered Jan 17 '20 at 09:21

1

I had a similar problem when I needed to parse the time from server but I needed to convert this time to UTC format before storing this information int MySQL DB. This was my solution:

     Instant dateConverted = LocalDateTime
                            .parse(dateTime, DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss", Locale.ENGLISH))
                            .atZone(ZoneId.of("Europe/Bratislava")).toInstant();

     long epochTime = dateConverted.toEpochMilli() / 1000L;

Where dateTime is a String variable containing the date and time from server And I have used DateTimeFormatter to format my time to appropriate format. At the end I have added the zoneID of my timeZone and converted it to Instant

And at the end I have converted to seconds

answered Jan 17 '20 at 09:21

Šimon

338
1
4
14

Thanks simon. But Instant and LocalDateTime classses are not accessible – sherin shaf Jan 17 '20 at 12:08
Can you tell me why are they not accessible? Do you need to do a static import for them or your project does not allow to use these classes? – Šimon Jan 17 '20 at 13:03
@sherinshaf Which is your Java version? – Ole V.V. Jan 18 '20 at 21:32

score 0 · Answer 2 · answered Jan 17 '20 at 09:01

0

Try below code,

currentTime = Timestamp.valueOf(LocalDateTime.ofInstant(Instant.now(), ZoneOffset.UTC));

answered Jan 17 '20 at 09:01

Vivek

376
1
14

Thanks. But Instant and LocalDateTime is not accessible from my project – sherin shaf Jan 17 '20 at 12:08
Please refer https://stackoverflow.com/questions/508019/how-to-store-date-time-and-timestamps-in-utc-time-zone-with-jpa-and-hibernate – Vivek Jan 17 '20 at 12:20

score 0 · Answer 3 · answered Jan 17 '20 at 10:13

0

       SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm", Locale.getDefault());
       sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
    String localTime = sdf.format(new Date(your_time_stamp));
    Date date = new Date();
    try {
        date = sdf.parse(localTime);//get local date
    } catch (ParseException e) {
        e.printStackTrace();
    }

answered Jan 17 '20 at 10:13

Kukadiya Anil

116
2
7

Thanks for your answer. But i need to convert the timestamp with @Version annotation to UTC timezone – sherin shaf Jan 17 '20 at 12:07
Please don’t teach the young ones to use the long outdated and notoriously troublesome `SimpleDateFormat` class. At least not as the first option. And not without any reservation. Today we have so much better in [`java.time`, the modern Java date and time API,](https://docs.oracle.com/javase/tutorial/datetime/) and its `DateTimeFormatter`. – Ole V.V. Jan 18 '20 at 21:32

How can we convert Timestamp datatype in Java to UTC timezone in JPA entity Java?

3 Answers3