I'm getting below exception while converting date string from ISO to UTC format in java, what I'm doing wrong here? Please find my code below:
Test.java
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;
public class Test {
public static void main(String[] args) {
String date="2020-11-02T07:00:00.114";
String result = LocalDateTime.parse(date, DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss")).atOffset(ZoneOffset.UTC).toString();
System.out.println("result: "+result);
}
}
Exception:
Exception in thread "main" java.time.format.DateTimeParseException: Text '2020-11-02T07:00:00.114' could not be parsed, unparsed text found at index 19
at java.base/java.time.format.DateTimeFormatter.parseResolved0(DateTimeFormatter.java:2049)
at java.base/java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1948)
at java.base/java.time.LocalDateTime.parse(LocalDateTime.java:492)
at test.service.Test.main(Test.java:11)
tl;dr
LocalDateTime
.parse( "2020-11-02T07:00:00.114" )
.atOffset( ZoneOffset.UTC )
.toString()
2020-11-02T07:00:00.114Z
Details
You said:
converting date string from ISO to UTC format
That does not exactly make sense.
There is an ISO 8601 standard defining sensible formats for exchanging date-time values textually. These standard formats are used by default when parsing/generating text.
There is no such thing as "UTC format". UTC is the temporal prime meridian, against which all time zones are defined. The rules for a time zone specify an offset-from-UTC in effect as a number of hours-minutes-seconds ahead or behind UTC. But this has nothing to with "formats" of text.
As for parsing your input string as a LocalDateTime object, there is no need to bother with defining a formatting pattern. Your string complies with ISO 8601, so it can be parsed directly.
LocalDateTime ldt = LocalDateTime.parse( "2020-11-02T07:00:00.114" ) ;
Your string, and a LocalDateTime object, represent a date with a time-of-day. But both lack the context of a time zone or offset-from-UTC.
Apparently you know that the publisher of your input string intended that to be a moment as seen from an offset of zero hours-minutes-seconds from UTC. So we can assign a ZoneOffset to get OffsetDateTime object.
OffsetDateTime odt = ldt.atOffset( ZoneOffset.UTC ) ;
To generate text representing that moment in ISO 8601 format, simply call toString.
String output = odt.toString() ;
See this code run live at Ideone.com.
2020-11-02T07:00:00.114Z
Notice the Z on the end, pronounced “Zulu”. That is an abbreviation for an offset of zero, +00:00.
Your pattern ends in ss, in other words: In seconds. Your input then has still more stuff.
DateTimeFormatter doesn't take a wild stab at it - it either matches properly or it does not parse. It looks like those are intended to be milliseconds; toss .SSS at the end of your pattern.
You are giving the format of:
yyyy-MM-dd'T'HH:mm:ss
However are specifying a string with fractions of a second 2020-11-02T07:00:00.114.
That is parsing whole seconds, but there is still more in the time string.
You need format of:
yyyy-MM-dd'T'HH:mm:ss.SSS
Related
I am trying to convert the value 2022-04-30 14:34:52.900426+00:00 an instance of LocalDateTime. I have written the following code:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSSSSS'Z'");
I am getting the following error
could not be parsed at index 26
What should my formatter string be?
tl;dr
OffsetDateTime // Use `OffsetDateTime`, not `LocalDateTime`, to represent a date with time and offset.
.parse(
"2022-04-30 14:34:52.900426+00:00" // Almost in ISO 8601 format.
.replace( " " , "T" ) // Replace SPACE with T to comply with ISO 8691.
)
See this code run live at IdeOne.com.
Wrong class, use OffsetDateTime, not LocalDateTime
LocalDateTime is exactly the wing class to use in this case. That represents a date with time-of-day. But your input indicates a date with time-of-day and an offset-from-UTC. The +00:00 means an offset of zero hours-minutes-seconds from UTC.
So parse that input as a OffsetDateTime object instead.
Rather than define a formatting pattern, I suggest merely replacing the SPACE in the middle with a T to comply with the ISO 8601 standard used by default in the java.time classes when parsing/generating text.
String input = "2022-04-30 14:34:52.900426+00:00".replace( " " , "T" ) ;
OffsetDateTime odt = OffsetDateTime.parse( input ) ;
It's not working because the UTC Time offsets hasn't been written properly. It should look like this with a custom DateTimeFormatter:
//Custom DatTimeFormatter
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSSSSSZZZZZ");
formatter.parse("2022-04-30 14:34:52.900426+00:00");
You could either use the predefined ISO_OFFSET_DATE_TIME DatTimeFormatter only by replacing the space between date and time with a capital T, as the standard requires.
//Predefined DateTimeFormatter
DateTimeFormatter.ISO_OFFSET_DATE_TIME.parse("2022-04-30T14:34:52.900426+00:00");
Besides, to answer your question under #Taco Jan Osinga's reply:
No, it is not correct to use "+00:00" to just match the datetime you're trying to parse. That custom DateTimeFormatter you would build would only match datetime referring to your local TimeZone; thus it won't work with datetime from different areas.
Have you tried "yyyy-MM-dd HH:mm:ss.SSSSSS+00:00"?
I've tried all sorts of different conversions with different Java formatters but I'm still not having any luck with something that seems simple.
I have a string that is a date/time in UTC. I'm trying to convert that to another time zone. Is any one able to tell me why the below isn't working? The time zone is changing but it's not changing the right way.
Updated: (though it doesn't seem like I'm setting the time zone to UTC properly as the conversion isn't correct either).
String dateInput = "2021-02-16 20:57:43";
SimpleDateFormat mdyUtc = new SimpleDateFormat ("yyyy-MM-dd hh:mm:ss");
mdyUtc.setTimeZone(TimeZone.getTimeZone("UTC");
Date utcOutput = mdyUtc.parse(dateInput);
SimpleDateFormat mdyOffset = new SimpleDateFormat ("yyyy-MM-dd hh:mm:ss");
mdyOffset.setTimeZone(TimeZone.getTimeZone("GMT-10:00");
Date localOutput = mdyOffset.parse(dateInput);
System.out.print("UTC date = " + utcOutput);
System.out.print("Changed date = " + localOutput);
Output:
UTC date = Tue Feb 16 15:57:43 EST 2021
Changed date = Wed Feb 17 01:57:43 EST 2021
java.time
The java.util date-time API and their formatting API, SimpleDateFormat are outdated and error-prone. It is recommended to stop using them completely and switch to the modern date-time API*.
Using the modern date-time API:
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
public class Main {
public static void main(String[] args) {
String dateInput = "2021-02-16 20:57:43";
// Replace ZoneId.systemDefault() with ZoneOffset.UTC if this date-time is in UTC
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("u-M-d H:m:s", Locale.ENGLISH)
.withZone(ZoneId.systemDefault());
ZonedDateTime zdt = ZonedDateTime.parse(dateInput, dtf);
ZonedDateTime result = zdt.withZoneSameInstant(ZoneId.of("GMT-10:00"));
System.out.println(result);
}
}
Output:
2021-02-16T10:57:43-10:00[GMT-10:00]
ONLINE DEMO
Learn more about the modern date-time API from Trail: Date Time.
Can I get java.util.Date from ZonedDateTime?
If at all you need to use java.util.Date, you can convert ZonedDateTime into it as follows:
Date date = Date.from(result.toInstant());
Note that the java.util.Date object is not a real date-time object like the modern date-time types; rather, it represents the number of milliseconds since the standard base time known as "the epoch", namely January 1, 1970, 00:00:00 GMT (or UTC). When you print an object of java.util.Date, its toString method returns the date-time in the JVM's timezone, calculated from this milliseconds value. If you need to print the date-time in a different timezone, you will need to set the timezone to SimpleDateFormat and obtain the formatted string from it.
* For any reason, if you have to stick to Java 6 or Java 7, you can use ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.
tl;dr
LocalDateTime // Represent a date with time-of-day but lacking the context of a time zone or offset-from-UTC.
.parse( // Interpret some text in order to build a date-time object.
"2021-02-16 20:57:43".replace( " " , "T" ) // Convert to standard ISO 8601 string to parse by default without needing to specify a formatting pattern.
) // Returns a `LocalDateTime` object.
.atOffset( // Place that date with time into the context of an offset. Determines a moment, a specific point on the timeline.
ZoneOffset.UTC // A constant for an offset of zero hours-minutes-seconds.
) // Returns an `OffsetDateTime` object.
.atZoneSameInstant( // Adjust the view of this moment as seen in the wall-clock time of some other time zone. Still the same moment, same point on the timeline.
ZoneId.of( "Pacific/Honolulu" ) // Use a time zone, if known, rather than a mere offset.
) // Returns a `ZonedDateTime` object.
.toString() // Generate text representing this moment in standard ISO 8601 format extended to append the time zone name in square brackets.
See this code run live at IdeOne.com.
2021-02-16T10:57:43-10:00[Pacific/Honolulu]
Details
The Answer by Avinash is correct, using a DateTimeFormatter with an assigned ZoneId. That works, but I prefer keeping the zone assignment separate from the formatter, to be more explicit to someone reading the code. This is only about my preference, not about correctness; both Answers are equally correct.
Parse your input as a LocalDateTime, as the input represents a date with time-of-day but lacks any indication of offset or time zone.
By default, the java.time classes use standard text formats defined in ISO 8601. If an input complies, no need to specify a formatting pattern. To comply, replace your input’s SPACE character in the middle with a T.
String input = "2021-02-16 20:57:43".replace( " " , "T" ) ;
LocalDateTime ldt = LocalDateTime.parse( input ) ;
You said you know for certain that input was meant to represent a date with time as seen in UTC, having an offset-from-UTC of zero hours-minutes-seconds. So we can apply an offset of zero using ZoneOffset to produce a OffsetDateTime.
Also, I suggest you educate the publisher of your data feed about using ISO 8601 formats to communicate that offset-of-zero fact by appending a Z (as well as using T in the middle).
OffsetDateTime odt = ldt.atOffset( ZoneOffset.UTC ) ; // Place date with time into context of an offset of zero.
Lastly, you said you want to adjust that moment to another time zone. Apply a ZoneId to get a ZonedDateTime object.
Actually, you specified an offset of "GMT-10:00". But it is better to use a time zone if known rather than a mere offset. A time zone is a history of past, present, and future changes to the offset used by the people of a particular region.
I will guess you want Hawaii time, Pacific/Honolulu.
ZoneId z = ZoneId.of( "Pacific/Honolulu" ) ;
ZonedDateTime zdt = odt.atZoneSameInstant( z ) ;
The java.util.Date API is deprecated; you should look into the new Date and Time APIs around LocalTime et al.
That said, if you want to keep the old code: It is a bit brittle. Your initial date input does not specify a time zone, so you'll probably get the system's time zone. You should specify a time zone --- if the expected input is UTC, say so.
Then you need to specify the time zone either in an hour offset or with a name, not both.
When I change your code to use
mdyOffset.setTimeZone(TimeZone.getTimeZone("-10:00"));
I get
Changed date = Tue Feb 16 14:57:43 CST 2021
which seems to fit, as I'm on CST (currently 6 hours after GMT), so 20:57:43 minus 6 is 14:57:43. Again, this is displayed in my local time zone. You may have to use a DateFormat to adjust the output as needed.
I want to add a Z at the end of DateTimeFormatter ISO_DATE_TIME in Java not hard coded
String sample = "2018-05-11T13:35:11Z";
DateTimeFormatter df = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss[.SSS][XXX][X]");
DateTimeFormatter df1 = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss'Z'");
LocalDateTime newLocalDateTime = LocalDateTime.parse(sample, df1);
System.out.println(newLocalDateTime.toString());
Output is:
2018-05-11T13:35:11
I want the output to be 2018-05-11T13:35:11Z
You are calling toString() of your LocalDateTime, you should be calling format. Change
System.out.println(newLocalDateTime.toString());
to
System.out.println(newLocalDateTime.format(df1));
Outputs
2018-05-11T13:35:11Z
If you want the output to have a time zone offset like Z, you should use OffsetDateTime or ZonedDateTime.
LocalDateTime ldt = LocalDateTime.parse("2018-05-11T13:35:11");
OffsetDateTime odt = ldt.atOffset(ZoneOffset.UTC);
System.out.println(odt); // prints: 2018-05-11T13:35:11Z
ZonedDateTime zdt = ldt.atZone(ZoneOffset.UTC);
System.out.println(zdt); // prints: 2018-05-11T13:35:11Z
As you can see, the toString() method will return the date in the format you requested.
You shouldn’t use LocalDateTime. Use OffsetDateTime. And you may need no formatter.
String sample = "2018-05-11T13:35:11Z";
OffsetDateTime dateTime = OffsetDateTime.parse(sample)
.withOffsetSameInstant(ZoneOffset.UTC);
System.out.println(dateTime.toString());
Output from this snippet is the dsesired:
2018-05-11T13:35:11Z
The call to withOffsetSameInstant() makes sure that the date and time are in UTC even if the input had not been. I am using OffsetDateTime.toString() to produce the output string. I am exploiting the fact that both your sample string and your desired output are in ISO 8601 format. OffsetDateTime and the other classes from java.time parse ISO 8601 format as their default, that is, without any explicit formatter, and produce ISO 8601 format from their toString methods.
OffsetDateTime.toString() on one hand will leave out the seconds if they are 0, will on the other hand include a fraction of second if it is non-zero (all of this agress with ISO 8601). If you don’t want this, you do need a formatter. For example:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd'T'HH:mm:ssX");
System.out.println(dateTime.format(formatter));
You are correct, you should not hardcode Z as a literal in the format pattern string. Z signifies an offset of zero from UTC. Use format pattern letter X to output the offset so you are sure the offset is always correct. This will print an offset of zero as Z.
A LocalDateTime doesn’t keep a UTC offset, so when parsing into one your are losing information. Don’t do this. Parse into an OffsetDateTime to pick up all the information from the string.
Link: Wikipedia article: ISO 8601
This question already has answers here:
Parsing ISO-8601 DateTime with offset with colon in Java
(4 answers)
String date into Epoch time
(4 answers)
Closed 3 years ago.
I have this format:
2011-10-10T01:45:20+00:00
I tried using LocalDateTime.parse("2011-10-10T01:45:20+00:00")
but I got error:
java.time.format.DateTimeParseEception: Text '2011-10-10T01:45:20+00:00' could not be parse, unparsed text found
The default formatter is DateTimeFormatter.ISO_LOCAL_DATE_TIME : '2011-12-03T10:15:30', the offset is not in,
You may parse using OffsetDateTime class that uses DateTimeFormatter.ISO_OFFSET_DATE_TIME : '2011-12-03T10:15:30+01:00' as formatter
OffsetDateTime.parse("2011-10-10T01:45:20+00:00") // print 2011-10-10T01:45:20Z
You can still use LocalDateTime but you need to specify the formatter
LocalDateTime.parse("2011-10-10T01:45:20+00:00", DateTimeFormatter.ISO_OFFSET_DATE_TIME); // 2011-10-10T01:45:20
Oracle Documentation
tl;dr
OffsetDateTime.parse( "2011-10-10T01:45:20+00:00" )
Wrong class
The LocalDateTime class is not appropriate to your input. That class represents only a date and a time-of-day but without any offset-from-UTC or time zone, so it does not represent a moment, is not a point on the timeline.
Your input string in contrast represents a moment, with an offset-from-UTC of zero hours-minutes-seconds: +00:00
OffsetDateTime
Correct class for your input is OffsetDateTime.
Your input string is in standard ISO 8601 format. These standard formats are used by default in the java.time classes. So no need to specify a formatting pattern.
OffsetDateTime odt = OffsetDateTime.parse( "2011-10-10T01:45:20+00:00" ) ;
See this code run live at IdeOne.com.
odt.toString(): 2011-10-10T01:45:20Z
FYI, the difference between offset and zone:
An offset-from-UTC is merely a number of hours-minutes-seconds. Nothing more. Represented by ZoneOffset class.
A time zone is much more. A time zone is a history of past, present, and future changes to the offset used by the people of a particular region. A time zone carries a name in Continent/Region format such as America/Montreal or Africa/Tunis. Represented by ZoneId class.
You could provide ISO date formatter in the parse method like this
import java.time.format.DateTimeFormatter
LocalDate.parse("2011-10-10T01:45:20+00:00", DateTimeFormatter.ISO_DATE_TIME)
My client sends me dates in ISO8601 which sometimes contains millisecond with zone and sometimes without millisecond and zone.
for example: 2019-05-01T06:55:43+01:00, 2019-05-01T06:55
I am using new time Java 8 API(LocalDateTime, DateTimeFormatter etc).
I didn't find a Date class with formatter which can handle both, with millisecond and zone and without this.
I am trying do do input date validation by using a single format
DateTimeFormatter formatter = DateTimeFormatter.ofPattern(templateFormat, locale);
try {
ldt = LocalDateTime.parse(context, formatter );
String result = ldt.format(formatter);
return result.equals(context);
} catch (DateTimeParseException e) {
try {
LocalDate ld = LocalDate.parse(context, formatter );
String result = ld.format(formatter);
return result.equals(context);
I am asking if there is a formatter which caches both, i can use multiple date classes, and if i fail continue to the next, for example (LocalDateTime, LocalDate, OffsetDateTime) but i need to use a single formatter
Different types
As Ole V.V. commented, your inputs:
2019-05-01T06:55:43+01:00
2019-05-01T06:55
…are two different animals.
The first represents a moment, a specific point on the timeline. The value includes three pieces of information:
date
time-of-day
offset-from-UTC
The second input has only a date and time-of-day. It lacks the context of a time zone or offset-from-UTC. So this value does not represent a moment. It is not a point on the timeline. This value represents potential moments along a range of about 26-27 hours, the range of time zones around the globe. Does the second mean 6 AM in Tokyo? Or Paris, when 6 AM occurs several hours later? Or even more hours later when 6 AM arrives in Québec?
So your data source is confused or broken if it is feeding you an arbitrary mix of these values. I suggest consulting with the publisher of that data to determine their intent, and perhaps educate them about the difference in meaning.
Parsing
for example: 2019-05-01T06:55:43+01:00, 2019-05-01T06:55
To answer your specific question:
Parse the first as a OffsetDateTime.
Parse the second as a LocalDateTime.
Trap for the DateTimeParseException. If thrown when parsing for one class, try parsing with the other class.
Both inputs are in standard ISO 8601 format. The java.time classes use the standard formats by default when parsing/generating strings. So no need to specify formatting patterns.
try {
OffsetDateTime odt = OffsetDateTime.parse( input ) ;
…
} catch ( DateTimeParseException e ) {
LocalDateTime ldt = LocalDateTime.parse( input ) ;
…
}