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Parsing date with timezone from a string

Quick (I suppose) question. How to parse string like that "2018-07-22 +3:00" to OffsetDateTime (setting time to 0:0:0.0)?
DateTimeFormatter formatter =cDateTimeFormatter.ofPattern("yyyy-MM-dd xxx");
OffsetDateTime dt = OffsetDateTime.parse("2007-07-21 +00:00", formatter);
java.time.format.DateTimeParseException: Text '2007-07-21 +00:00'
could not be parsed: Unable to obtain OffsetDateTime from
TemporalAccessor: {OffsetSeconds=0},ISO resolved to 2007-07-21 of type
java.time.format.Parsed

The trick here is to start by getting the TemporalAccessor:
TemporalAccessor ta = DateTimeFormatter.ofPattern("yyyy-MM-dd XXX").parse("2018-07-22 +03:00");
From there, you can extract a LocalDate and a ZoneOffset:
LocalDate date = LocalDate.from(ta);
ZoneOffset tz = ZoneOffset.from(ta);
And combine them like so:
ZonedDateTime zdt = date.atStartOfDay(tz);

An OffsetDateTime requires a time-of-day, but your format string doesn't supply that, so you need to tell the DateTimeFormatter to default time-of-day to midnight.
Also, offset +3:00 is invalid, since hour must be 2-digit, which means you need to fix that first.
This will do both:
public static OffsetDateTime parse(String text) {
// Fix 1-digit offset hour
String s = text.replaceFirst("( [+-])(\\d:\\d\\d)$", "$10$2");
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.appendPattern("uuuu-MM-dd xxx")
.parseDefaulting(ChronoField.HOUR_OF_DAY, 0)
.toFormatter();
return OffsetDateTime.parse(s, formatter);
}
Test
System.out.println(parse("2018-07-22 +3:00"));
System.out.println(parse("2018-07-22 +03:00"));
System.out.println(parse("2007-07-21 +00:00"));
Output
2018-07-22T00:00+03:00
2018-07-22T00:00+03:00
2007-07-21T00:00Z

Month Year In String to Date Java 8 [duplicate]

This question already has answers here:
How to convert date from MM/YYYY to MM/DD/YYYY in Java
(4 answers)
Closed 4 years ago.
DateTimeFormatter dateFormat = DateTimeFormatter.ofPattern("MM/yyyy");
LocalDate parsedDate = LocalDate.parse(entryOne.getKey(), dateFormat)
Getting exception
Text '03/2018' could not be parsed: Unable to obtain LocalDate from TemporalAccessor:
How to parse this string and convert to Date using Java 8 having default first day of the month. Something what we do using.
TemporalAdjusters.firstDayOfMonth()

You have two choices for converting a MM/yyyy string into a LocalDate:
Parse as YearMonth then convert to LocalDate:
String date = "04/2018";
DateTimeFormatter dateFormat = DateTimeFormatter.ofPattern("MM/yyyy");
YearMonth yearMonth = YearMonth.parse(date, dateFormat);
LocalDate parsedDate = yearMonth.atDay(1);
System.out.println(parsedDate); // prints: 2018-04-01
Use a DateTimeFormatter with a default day-of-month defined:
String date = "04/2018";
DateTimeFormatter dateFormat = new DateTimeFormatterBuilder()
.appendPattern("MM/yyyy")
.parseDefaulting(ChronoField.DAY_OF_MONTH, 1)
.toFormatter();
LocalDate parsedDate = LocalDate.parse(date, dateFormat);
System.out.println(parsedDate); // prints: 2018-04-01

Here's what works for me:
String dateAsString = "03/2018";
DateTimeFormatter fmt = DateTimeFormat.forPattern("MM/yyyy");
DateTime dt = fmt.parseDateTime(dateAsString);
LocalDateTime ldt = new LocalDateTime(dt);
int dayOfWeek = ldt.getDayOfWeek(); //has value of 4 since Thursday was the first day of March

Java: Unable to obtain LocalDate from TemporalAccessor

I am trying to change the format of a String date from EEEE MMMM d to MM/d/yyyy by, first, converting it into a LocalDate and then applying a formatter of a different pattern to the LocalDate before parsing it into String again.
Here's my code:
private String convertDate(String stringDate)
{
//from EEEE MMMM d -> MM/dd/yyyy
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.parseCaseInsensitive()
.append(DateTimeFormatter.ofPattern("EEEE MMMM d"))
.toFormatter();
LocalDate parsedDate = LocalDate.parse(stringDate, formatter);
DateTimeFormatter formatter2 = DateTimeFormatter.ofPattern("MM/d/yyyy");
String formattedStringDate = parsedDate.format(formatter2);
return formattedStringDate;
}
However, I get this exception message that I don't really understand:
Exception in thread "main" java.time.format.DateTimeParseException: Text 'TUESDAY JULY 25' could not be parsed: Unable to obtain LocalDate from TemporalAccessor: {DayOfWeek=2, MonthOfYear=7, DayOfMonth=25},ISO of type java.time.format.Parsed
at java.time.format.DateTimeFormatter.createError(DateTimeFormatter.java:1920)

As the other answers already said, to create a LocalDate you need the year, which is not in the input String. It has only day, month and day of the week.
To get the full LocalDate, you need to parse the day and month and find a year in which this day/month combination matches the day of the week.
Of course you could ignore the day of the week and assume that the date is always in the current year; in this case, the other answers already provided the solution. But if you want to find the year that exactly matches the day of the week, you must loop until you find it.
I'm also creating a formatter with a java.util.Locale, to make it explicit that I want month and day of week names in English. If you don't specify a locale, it uses the system's default, and it's not guaranteed to always be English (and it can be changed without notice, even at runtime).
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.parseCaseInsensitive()
.append(DateTimeFormatter.ofPattern("EEEE MMMM d"))
// use English Locale to correctly parse month and day of week
.toFormatter(Locale.ENGLISH);
// parse input
TemporalAccessor parsed = formatter.parse("TUESDAY JULY 25");
// get month and day
MonthDay md = MonthDay.from(parsed);
// get day of week
DayOfWeek dow = DayOfWeek.from(parsed);
LocalDate date;
// start with some arbitrary year, stop at some arbitrary value
for(int year = 2017; year > 1970; year--) {
// get day and month at the year
date = md.atYear(year);
// check if the day of week is the same
if (date.getDayOfWeek() == dow) {
// found: 'date' is the correct LocalDate
break;
}
}
In this example, I started at year 2017 and tried to find a date until back to 1970, but you can adapt to the values that fits your use cases.
You can also get the current year (instead of some fixed arbitrary value) by using Year.now().getValue().

The documentation for LocalDate says, that
LocalDate is an immutable date-time object that represents a date,
often viewed as year-month-day. For example, the value "2nd October
2007" can be stored in a LocalDate.
In your case, the input String is missing an important component of LocalDate , i.e the year. What you have basically is month and day. So, you can use a class suited to that MonthDay. Using that your code can be modified to :
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.parseCaseInsensitive()
.append(DateTimeFormatter.ofPattern("EEEE MMMM d"))
.toFormatter();
MonthDay monthDay = MonthDay.parse(stringDate, formatter);
LocalDate parsedDate = monthDay.atYear(2017); // or whatever year you want it at
DateTimeFormatter formatter2 = DateTimeFormatter.ofPattern("MM/d/yyyy");
String formattedStringDate = parsedDate.format(formatter2);
System.out.println(formattedStringDate); //For "TUESDAY JULY 25" input, it gives the output 07/25/2017

Here is the minor change which you need to implement:
private static String convertDate(String stringDate)
{
//from EEEE MMMM d -> MM/dd/yyyy
DateTimeFormatter formatter = new DateTimeFormatterBuilder().appendPattern("EEEE MMMM dd")
.parseDefaulting(ChronoField.YEAR, 2017)
.toFormatter();
LocalDate parsedDate = LocalDate.parse(stringDate, formatter);
DateTimeFormatter formatter2 = DateTimeFormatter.ofPattern("MM/d/yyyy");
String formattedStringDate = parsedDate.format(formatter2);
return formattedStringDate;
}
Add the default chronological year in the formatter using .parseDefaulting(ChronoField.YEAR, 2017)
Call the method using the argument "Tuesday July 25" like this convertDate("Tuesday July 25");

Another option is to do the following (just like the other answers a bit hacky), assuming of course you want the date to fall in the current year:
LocalDate localDate = LocalDate.parse(stringDate + " " +LocalDate.now().getYear(), DateTimeFormatter.ofPattern("EEEE MMMM d");

Java 8: How to parse expiration date of debit card?

It is really easy to parse expiration date of debit/credit card with Joda time:
org.joda.time.format.DateTimeFormatter dateTimeFormatter = org.joda.time.format.DateTimeFormat.forPattern("MMyy").withZone(DateTimeZone.forID("UTC"));
org.joda.time.DateTime jodaDateTime = dateTimeFormatter.parseDateTime("0216");
System.out.println(jodaDateTime);
Out: 2016-02-01T00:00:00.000Z
I tried to do the same but with Java Time API:
java.time.format.DateTimeFormatter formatter = java.time.format.DateTimeFormatter.ofPattern("MMyy").withZone(ZoneId.of("UTC"));
java.time.LocalDate localDate = java.time.LocalDate.parse("0216", formatter);
System.out.println(localDate);
Output:
Caused by: java.time.DateTimeException: Unable to obtain LocalDate
from TemporalAccessor: {MonthOfYear=2, Year=2016},ISO,UTC of type
java.time.format.Parsed at
java.time.LocalDate.from(LocalDate.java:368) at
java.time.format.Parsed.query(Parsed.java:226) at
java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1851)
... 30 more
Where I made a mistake and how to resolve it?

A LocalDate represents date that is composed of a year, a month and a day. You can't make a LocalDate if you don't have those three fields defined. In this case, you are parsing a month and a year, but there is no day. As such, you can't parse it in a LocalDate.
If the day is irrelevant, you could parse it into a YearMonth object:
YearMonth is an immutable date-time object that represents the combination of a year and month.
public static void main(String[] args) {
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MMyy").withZone(ZoneId.of("UTC"));
YearMonth yearMonth = YearMonth.parse("0216", formatter);
System.out.println(yearMonth); // prints "2016-02"
}
You could then transform this YearMonth into a LocalDate by adjusting it to the first day of the month for example:
LocalDate localDate = yearMonth.atDay(1);

convert shortdate to LocalDate

Hi i have a short date format with me in the pattern E dd/MM , Is there any way i can convert it to LocalDate.
String date = "Thu 07/05";
String formatter = "E dd/MM";
final DateTimeFormatter formatter = DateTimeFormatter.ofPattern(pattern);
final LocalDate localDate = LocalDate.parse(date, formatter);`
But it throws an exception java.time.format.DateTimeParseException: Text 'Thu 07/05' could not be parsed: Unable to obtain LocalDate from TemporalAccessor: {MonthOfYear=5, DayOfMonth=7, DayOfWeek=4},ISO of type java.time.format.Parsed
Is there any way we can fix this issue ?

All you have is a month and a day - so you can create a MonthDay (to create a LocalDate you would also need a year):
MonthDay md = MonthDay.parse(date, formatter);
If you want a LocalDate, you can use the MonthDay as a starting point:
int year = Year.now().getValue();
LocalDate localDate = md.atYear(year);
Or alternatively you can use a default year in your formatter:
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.appendPattern(pattern)
.parseDefaulting(ChronoField.YEAR, year)
.toFormatter(Locale.US);
LocalDate localDate = LocalDate.parse(date, formatter);
The benefit of this method is that it will also check that the day of week (Thursday) is correct.