Current Time in Iso 8601 Format

How to get current moment in ISO 8601 format with date, hour, and minute?

Use SimpleDateFormat to format any Date object you want:

TimeZone tz = TimeZone.getTimeZone("UTC");
DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm'Z'"); // Quoted "Z" to indicate UTC, no timezone offset
df.setTimeZone(tz);
String nowAsISO = df.format(new Date());

Using a new Date() as shown above will format the current time.

How to print the current time and date in ISO date format in java?

In java 8 you can use the new java.time api:

OffsetDateTime now = OffsetDateTime.now();
DateTimeFormatter formatter = DateTimeFormatter.ISO_DATE_TIME;
System.out.println(formatter.format(now)); // e.g. 2018-04-30T08:43:41.4746758+02:00

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The above uses the standard ISO data time formatter. You can also truncate to milliseconds with:

OffsetDateTime now = OffsetDateTime.now().truncatedTo(ChronoUnit.MILLIS);

Which yields something like (only 3 digits after the dot):

2018-04-30T08:54:54.238+02:00

Convert date and time to Iso 8601 in Kotlin

Try with this code:

val date = Calendar.getInstance().apply {
    set(Calendar.YEAR, year)
    set(Calendar.MONTH, month)
    set(Calendar.DAY_OF_MONTH, day)
    set(Calendar.HOUR_OF_DAY, hour)
    set(Calendar.MINUTE, minute)
}.time 
val formattedDate = SimpleDateFormat("yyyy-MM-dd'T'HH:mm'Z'").format(date)

How to ISO 8601 format a Date with Timezone Offset in JavaScript?

Here's a simple helper function that will format JS dates for you.

function toIsoString(date) {
  var tzo = -date.getTimezoneOffset(),
      dif = tzo >= 0 ? '+' : '-',
      pad = function(num) {
          return (num < 10 ? '0' : '') + num;
      };

  return date.getFullYear() +
      '-' + pad(date.getMonth() + 1) +
      '-' + pad(date.getDate()) +
      'T' + pad(date.getHours()) +
      ':' + pad(date.getMinutes()) +
      ':' + pad(date.getSeconds()) +
      dif + pad(Math.floor(Math.abs(tzo) / 60)) +
      ':' + pad(Math.abs(tzo) % 60);
}

var dt = new Date();
console.log(toIsoString(dt));

Current time in ISO 8601 format

as.POSIXlt (and as.POSIXct) are for input. Use either format or strftime for output. See ?strftime for details on format strings:

 tm <- as.POSIXlt(Sys.time(), "UTC")
 strftime(tm , "%Y-%m-%dT%H:%M:%S%z")
#[1] "2015-04-08T15:11:22+0000"

The third parameter of as.POSIXlt, format, is used when the first parameter is a string-like value that needs to be parsed. Since we are passing in a Date value from Sys.time, the format is ignored.

I don't think that the colon in the timezone output is requirement of the ISO 8601 format but I could be wrong on that point. The help page says the standard is POSIX 1003.1. May need to put in the colon with a regex substitution if needed.

After looking at http://dotat.at/tmp/ISO_8601-2004_E.pdf I see that there is no colon in the "basic" format" timezone representation, but there is one in the "extended format".

Converting ISO 8601-compliant String to java.util.Date

Unfortunately, the time zone formats available to SimpleDateFormat (Java 6 and earlier) are not ISO 8601 compliant. SimpleDateFormat understands time zone strings like "GMT+01:00" or "+0100", the latter according to RFC # 822.

Even if Java 7 added support for time zone descriptors according to ISO 8601, SimpleDateFormat is still not able to properly parse a complete date string, as it has no support for optional parts.

Reformatting your input string using regexp is certainly one possibility, but the replacement rules are not as simple as in your question:

• Some time zones are not full hours off UTC, so the string does not necessarily end with ":00".
• ISO8601 allows only the number of hours to be included in the time zone, so "+01" is equivalent to "+01:00"
• ISO8601 allows the usage of "Z" to indicate UTC instead of "+00:00".

The easier solution is possibly to use the data type converter in JAXB, since JAXB must be able to parse ISO8601 date string according to the XML Schema specification. javax.xml.bind.DatatypeConverter.parseDateTime("2010-01-01T12:00:00Z") will give you a Calendar object and you can simply use getTime() on it, if you need a Date object.

You could probably use Joda-Time as well, but I don't know why you should bother with that (Update 2022; maybe because the entire javax.xml.bind section is missing from Android's javax.xml package).

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