Argthtjtr

I converted an Instant to LocalDateTime in Java with Spring Boot as seen below

LocalDateTime.ofInstant(timeInUtc, zoneId);

In my test I got a Regex to check whether my resource returns a Json with a LocalDateTime. The Regex expects a JSON value in the format:

 2018-11-15T08:38:49.382

But it looks like the trailing zero is removed, meaning instead of

2018-11-15T08:38:49.380

which would comply to the regex, I get

 2018-11-15T08:38:49.38

How can I make sure that the trailing zero is not removed?

Thanks in advance!

Formatting the date would help to retain the trailing zero

DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS")

Output looks like below:

2018-11-15T08:03:45.580

The code below:

public class Post2 {



    public static void main(String args) {



        String date = LocalDateTime.ofInstant(Instant.now(), ZoneId.of("UTC"))

           .format(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS"));

        System.out.println(date);



    }

}

EDIT
Adding regex matching to match date time with and without milli seconds.

        String regex = "^\d\d\d\d-(0?[1-9]|1[0-2])-(0?[1-9]|[12][0-9]|3[01]) (00|[0-9]|1[0-9]|2[0-3]):([0-9]|[0-5][0-9]):([0-9]|[0-5][0-9])(\.{0,1}[0-9]{1,3})$";



        String str1 = "2015-1-11 13:57:24";



        String str2 = "2015-1-11 13:57:24.0";

        String str3 = "2015-1-11 13:57:24.00";

        String str4 = "2015-1-11 13:57:24.000";

        String str5 = "2015-1-11 13:57:24.1";

        String str6 = "2015-1-11 13:57:24.12";

        String str7 = "2015-1-11 13:57:24.1222";

        String str8 = "2015-1-11 13:57:24.02";



        System.out.println( str1.matches(regex));

        System.out.println(str2.matches(regex));

        System.out.println(str3.matches(regex));

        System.out.println(str4.matches(regex));

        System.out.println(str5.matches(regex));

        System.out.println(str6.matches(regex));

        System.out.println(str7.matches(regex));

        System.out.println(str8.matches(regex));

output:

true

true

true

true

true

true

false

true