Scala/Java parse date unknown format

Question

I have the following code:

val dateString = "12/Sep/2017:11:25:29 +0200"
println(LocalDateTime.parse(
    dateString, 
    DateTimeFormatter.ofPattern("dd/LLL/yyyy:HH:mm:ss X")
));

and the following error:

Exception in thread "main" java.time.format.DateTimeParseException:
Text '12/Sep/2017:11:25:29 +0200' could not be parsed at index 3

What is wrong in my format? I read https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html but do not find the correct one

EDIT1: "dd/MMM/yyyy:HH:mm:ss X" does not work either

[Never use SimpleDateFormat or DateTimeFormatter without a Locale](https://stackoverflow.com/a/65544056/10819573) — Arvind Kumar Avinash, Jun 10 '21 at 20:49
Does this answer your question? [java DateTimeFormatterBuilder fails on testtime \[duplicate\]](https://stackoverflow.com/questions/50526234/java-datetimeformatterbuilder-fails-on-testtime) — Ole V.V., Jun 11 '21 at 07:11

Alberto Sinigaglia · Answer 1 · 2021-06-10T20:40:04.213

3

You have to use M instead of L (L is for the numeric format):

"dd/MMM/yyyy:HH:mm:ss X"

You probably have also to set the Locale that java will use to interpret the month (probably your locale is not english)

LocalDateTime.parse("12/Sep/2017:11:25:29 +0200", DateTimeFormatter.ofPattern("dd/MMM/yyyy:HH:mm:ss X", Locale.ENGLISH));

This works for me (with the locale declared, probably also L will work fine)

edited Jun 10 '21 at 20:40

answered Jun 10 '21 at 20:17

Alberto Sinigaglia

12,097
2
20
48

maybe OF, but it might help: I use http://www.sdfonlinetester.info/ to test the format of the dates, to check if it's correct or not (is correct if the output of the website is the input that you are providing) – Alberto Sinigaglia Jun 10 '21 at 20:18
The doc say the opposite: " M/L month-of-year number/text 7; 07; Jul; July; J" and use MMM return the same error – Benjamin Jun 10 '21 at 20:21
and I am not sure SimpleDateFormat is equivalent to DateTimeFormatter for text month – Benjamin Jun 10 '21 at 20:22
1

@Benjamin The Javadoc also explains that `L` is for the “standalone” month name. Some languages vary the spelling depending on whether the month is used by itself or in combination. English is not one of those languages. – Basil Bourque Jun 10 '21 at 20:32
@BasilBourque ho OK thanks for the explanation. As I said "dd/MMM/yyyy:HH:mm:ss X" does not work either – Benjamin Jun 10 '21 at 20:35

Basil Bourque · Accepted Answer · 2021-06-11T00:06:38.260

The Answer by Sinigaglia is correct but insufficient. You should specify a Locale for which Sep is recognizable as a month name. An English-speaking locale is needed such as Locale.US.

If unspecified the JVM’s current default time zone is automatically implicitly applied. Sep is not a month name in Russian, French, Japanese, etc.

Tip: As a general rule, always specify explicitly your intended locale and time zone; use the optional arguments. Relying implicitly on the JVM’s current defaults can be problematic.

    Locale locale = Locale.US ;
    DateTimeFormatter f = DateTimeFormatter.ofPattern( "dd/MMM/yyyy:HH:mm:ss X" ).withLocale( locale ) ;
    String input = "12/Sep/2017:11:25:29 +0200" ;
    OffsetDateTime odt = OffsetDateTime.parse( input , f ) ;

    System.out.println( odt ) ;

See this code run live on IdeOne.com.

2017-09-12T11:25:29+02:00

As for your use of L, the Javadoc explains that L is for the “standalone” month name. Some languages vary the spelling depending on whether the month is used by itself or in combination. English is not one of those languages.

score 0 · Answer 3 · answered Jun 10 '21 at 20:25

0

Removing / from the input String should work. (Didn't check)

val dateString = "12 Sep 2017:11:25:29 +0200"

answered Jun 10 '21 at 20:25

dulvui

122
9

Why would i need to clean the date before parsing it? / is a well known character in dates formats as far as I know – Benjamin Jun 10 '21 at 20:32

Scala/Java parse date unknown format

3 Answers3