java.time.temporal.UnsupportedTemporalTypeException: Unsupported field: OffsetSeconds

Question

I am using the following functional Interface to make a general purpose custom date format converter.

@FunctionalInterface
public interface CustomDateFormatterInterface {
String convertStringToDate();
}

The Implementation of this functional Interface is as follows

CustomDateFormatterInterface customDateFormatterInterface = () -> {
                LocalDateTime localDateTime = LocalDateTime.now();
                DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ssZ")
                        .withLocale(Locale.getDefault())
                        .withZone(ZoneId.systemDefault());

                Instant now = Instant.now();

                String formatted = dateTimeFormatter.format(localDateTime);
                LocalDateTime parsed = dateTimeFormatter.parse(formatted, LocalDateTime::from);
                return parsed.toString();
            };

I want to get the following date format 2011-04-27T19:07:36+0000. But I am getting an exception. If I try to use the now Instant I am getting the output as

2020-12-29T15:44:34Z

What should I do can anyone tell me where I am going wrong? Let me know for any other things if needed.

Answer 1

use OffsetDateTime which has offset of the timezone and truncate it to seconds

A date-time with an offset from UTC/Greenwich in the ISO-8601 calendar system, such as 2007-12-03T10:15:30+01:00.

OffsetDateTime offsetDateTime = OffsetDateTime.now(ZoneId.of("Europe/Paris"));

offsetDateTime.truncatedTo(ChronoUnit.SECONDS).format(DateTimeFormatter.ISO_OFFSET_DATE_TIME); //2020-12-29T18:28:44+01:00

If you want a custom format the build it using DateTimeFormatterBuilder

OffsetDateTime offsetDateTime = OffsetDateTime.now(ZoneOffset.UTC);

DateTimeFormatter dateTimeFormatter = new DateTimeFormatterBuilder()
            .append(DateTimeFormatter.ISO_LOCAL_DATE_TIME)
            .appendOffset("+HHMM", "+0000")
            .toFormatter();
offsetDateTime.truncatedTo(ChronoUnit.SECONDS).format(dateTimeFormatter); //2020-12-29T17:36:51+0000