SimpleDateFormat is giving future date as formatted Date

Question

    String timestamp = "2020-05-22 12:58:04.517123+05:30"; 
    Date d = null;
    try {
        d = ext.parse(timestamp);
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } */
    Date date = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSSSSS").parse(timestamp);
    System.out.println(date);
    // o/p : Fri May 22 13:06:41 IST 2020

we can see that SimpleDateFormat is producing Future Date. What might be the reason ?

Your example data from first and last lines seem to be from two different scenarios. — Basil Bourque, May 26 '20 at 06:38
How many second is `517123ms` ? Maybe you mean `"2020-05-22 12:58:04.517+05:30"` — Scary Wombat, May 26 '20 at 06:39
Do you understand that `Date::toString` tells a lie? That method dynamically applies the JVM’s current default time zone while generating text to represent the value of the object. This has been covered many many times already on Stack Overflow. — Basil Bourque, May 26 '20 at 06:40
So what is the correct way to get the actual time in this case ? — Shailesh Jamloki, May 26 '20 at 06:42

Basil Bourque · Accepted Answer · 2020-05-26T14:50:48.137

2

`java.time.OffsetDateTime`

You have an input and a formatting pattern that both use microseconds. The Date type is limited to milliseconds.

You should not be using the terrible Date and SimpleDateFormat classes. Use only java.time classes.

Edit your input text to comply with the ISO 8601 standard. Replace the SPACE in the middle with T.

String input = "2020-05-22 12:58:04.517123+05:30".replace( " " , "T" ) ;
OffsetDateTime odt = OffsetDateTime.parse( input ) ;

edited May 26 '20 at 14:50

answered May 26 '20 at 06:46

Basil Bourque

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@RaviKumarRavanam No, I don’t know GIS. – Basil Bourque May 26 '20 at 06:55
@ScaryWombat Fixed, thanks. – Basil Bourque May 26 '20 at 06:56

score 2 · Answer 2 · answered May 26 '20 at 06:50

If you can use java.time for this, do it. Do it like in the answer given by @BasilBorque or provide a pattern that parses Strings of the given format directly without replacing the whitespace with a T to make it the ISO pattern:

public static void main(String[] args) {
    String timestamp = "2020-05-22 12:58:04.517123+05:30";
    // parse the string to an OffsetDateTime using a matching pattern
    OffsetDateTime odt = OffsetDateTime.parse(timestamp,
            DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSSSSSXXXXX"));
    // print the result in the default (ISO) pattern
    System.out.println(odt);
}

The result looks like

2020-05-22T12:58:04.517123+05:30

and is formattable in many different ways.

Pankaj · Answer 3 · 2020-05-26T07:26:32.807

1

In 12:58:04.517123+05:30 517123 is considered millisecond, which translates to roughly 8 minutes 37 seconds. That's the reason your time is changing. Another important aspect of Date is that it has no concept of timezone, it's merely tells no. of milliseconds from epoch. So when you do toString() it display time in JVM timezone.

edited May 26 '20 at 07:26

answered May 26 '20 at 06:46

Pankaj

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SimpleDateFormat is giving future date as formatted Date

3 Answers3

java.time.OffsetDateTime

`java.time.OffsetDateTime`