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String date convertion to Date Conversion [duplicate]

This question already has answers here:
display Java.util.Date in a specific format
(11 answers)
Get Date type object in format in java
(6 answers)
convert java.util.Date to java.util.Date with different formating in JAVA [duplicate]
(1 answer)
Closed 11 months ago.
My requirement is to convert the string "2019-04-25 07:06:42.790" to Date Object with same format as "2019-04-25 07:06:42.790".
I tried to do this, but it is always giving in String format.
String createDate = "2019-04-25 07:06:42.790";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS", Locale.US);
LocalDateTime localDateTime = LocalDateTime.parse(createDate, formatter);
System.out.println(formatter.format(localDateTime));
SimpleDateFormat formatter1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS", Locale.US);
formatter1.setTimeZone(TimeZone.getTimeZone("IST"));
Date date = formatter1.parse(createDate);
System.out.println(date);
String formattedDateString = formatter1.format(date);
System.out.println(formattedDateString);
Output from the above code:
2019-04-25 07:06:42.790
Thu Apr 25 07:06:42 IST 2019
2019-04-25 07:06:42.790

tl;dr
Date-time objects do not have a “format”.
Use only java.time classes.
LocalDateTime
.parse (
"2019-04-25 07:06:42.790"
.replace( " " , "T" )
)
.toString()
.replace( "T" , " " )
Details
You need to understand that date-time objects are not text. They don’t have a “format”. The do parse and generate text in various formats, but that text is always external.
Use only the java.time classes. Avoid legacy classes such as Date and Calendar.
Make your input comply with ISO 8601 standard.
String input = "2019-04-25 07:06:42.790".replace( " " , "T" ) ;
Parse as a LocalDateTime.
LocalDateTime ldt = LocalDateTime.parse ( input ) ;
To generate the same text as your input, call toString and replace the T with your desired SPACE character.
You could use a DateTimeFormatter rather than the string manipulations shown above. But in your specific case I recommend the string manipulations.

Custom format for java.time.LocalDate is throwing DateTimeParseException [duplicate]

This question already has answers here:
Unable to Convert String to localDate with custom pattern [duplicate]
(1 answer)
How to format LocalDate object to MM/dd/yyyy and have format persist
(4 answers)
Why am I getting a parse exception when I try to parse the current LocalDateTime [duplicate]
(2 answers)
Closed 1 year ago.
I would like to parse a date format YYYY-MM-DD into the following MMM dd, yyyy.
This is my part of code which is causing DateTimeParseException - >
DateTimeFormatter dateTimeFormatter1 = DateTimeFormatter.ofPattern("MMM dd, yyyy"); LocalDate localDate = LocalDate.parse("2002-10-01",dateTimeFormatter1);
The exception message when I try to parse the date with the given format is:
Method threw 'java.time.format.DateTimeParseException' exception. Text '2002-10-01' could not be parsed at index 0.

That's because 2002-10-01 is in format YYYY-MM-DD, so trying to parse (i.e. convert it to a LocalDate object) it with format MMM dd, yyyy isn't going to work.
You need two formats to do this:
DateTimeFormatter dateTimeFormatter1 = DateTimeFormatter.ofPattern("yyyy-MM-dd");
DateTimeFormatter dateTimeFormatter2 = DateTimeFormatter.ofPattern("MMM dd, yyyy");
LocalDate localDate = LocalDate.parse("2002-10-01",dateTimeFormatter1);
String newRepresentation = dateTimeFormatter2.format(localDate);
System.out.println(newRepresentation);

Your exception was caused by your specified parsing format "MMM dd, yyyy" not matching the input 2002-10-01.
You commented:
I would need to have it as an LocalDate object in MMM dd, yyyy format
A LocalDate does not have a “format”. Text has a format, but LocalDate is not text.
The LocalDate class can parse an incoming string to produce a LocalDate object. And a LocalDate object can generate a string that represents its value. But a LocalDate object itself is neither of those strings. LocalDate has its own internal representation of a date, the details of which do not concern us.
You said:
I would like to parse a date format YYYY-MM-DD
That format complies with the ISO 8601 standard. The java.time classes use those standard formats by default when parsing/generating text. So no need to specify a formatting pattern.
LocalDate ld = LocalDate.parse( "2002-10-01" ) ;
You said
… into the following MMM dd, yyyy.
Generally better to let java.time automatically localize rather than you hard-code a specific format.
Locale locale = Locale.US ;
DateTimeFormatter f = DateTimeFormatter.ofLocalizedDate( FormatStyle.MEDIUM ).withLocale( locale ) ;
String output = ld.format( f ) ;

Parse a String with week and year into a LocalDate [duplicate]

This question already has answers here:
How to parse date from string with year and week using java.time
(3 answers)
Closed 3 years ago.
The kind of String I want to parse : "36/2017", with 36 the week of the year, 2017 the year.
My code :
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.appendPattern("w/uuuu")
.parseDefaulting(ChronoField.DAY_OF_WEEK, 1)
.toFormatter();
LocalDate date = LocalDate.parse("36/2017", formatter);
I added a default day.
I have this message :
java.time.format.DateTimeParseException: Text '36/2017' could not be parsed: Unable to obtain LocalDate from TemporalAccessor: {WeekOfWeekBasedYear[WeekFields[MONDAY,4]]=36, Year=2017, DayOfWeek=1},ISO of type java.time.format.Parsed
Any idea ?
Thank you !

From the docs: https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html
You should use uppercase Y's if you are using weeks.
public static void main(String[] args) {
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
.appendPattern("w/YYYY")
.parseDefaulting(ChronoField.DAY_OF_WEEK, 1)
.toFormatter();
LocalDate date = LocalDate.parse("36/2017", formatter);
}

The pattern is wrong. You must set the following string
"w/YYYY"
DateTimeFormatter formatter = new
DateTimeFormatterBuilder()
.appendPattern("w/YYYY")
.parseDefaulting(ChronoField.DAY_OF_WEEK, 1)
.toFormatter();
LocalDate date = LocalDate.parse("36/2017", formatter);

Format ZonedDateTime [duplicate]

This question already has answers here:
Unable to obtain ZonedDateTime from TemporalAccessor using DateTimeFormatter and ZonedDateTime in Java 8
(5 answers)
Closed 4 years ago.
I need to format a ZonedDate time to format MM/dd/yyyy.
ZonedDateTime zonedDateTime = ZonedDateTime.now();
String date = DateTimeFormatter.ofPattern("MM/dd/yyyy").format(zonedDateTime);
ZonedDateTime zoneDate = ZonedDateTime.parse(date);
Getting error:
Exception in thread "main" java.time.format.DateTimeParseException: Text '12/05/2018' could not be parsed at index 0
Or if I convert my value to a String with the format I want and then try to parse it back a ZonedDate Time with my format once again:
DateTimeFormatter format = DateTimeFormatter.ofPattern("MM/dd/yyyy");
ZonedDateTime zonedDateTime = ZonedDateTime.now();
String date = DateTimeFormatter.ofPattern("MM/dd/yyyy").format(zonedDateTime);
ZonedDateTime zonedate = ZonedDateTime.parse(date, format);
I get error:
Exception in thread "main" java.time.format.DateTimeParseException: Text '12/05/2018' could not be parsed: Unable to obtain ZonedDateTime from TemporalAccessor: {},ISO resolved to 2018-12-05 of type java.time.format.Parsed
I've seen plenty of questions on this, but I keep getting these parsing errors

There are two problems. First, there is no zone information in the date, and second, there is no time information. You can convert it to a LocalDate:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MM/dd/yyyy");
ZonedDateTime zonedDateTime = ZonedDateTime.now();
String date = formatter.format(zonedDateTime);
LocalDate localdate = LocalDate.parse(date, formatter);
And you can convert a LocalDate to a ZonedDateTime by setting the time to the time at start of day, and the zone to the default system zone. Otherwise, you'd need to provide a time and a ZoneId of your choosing.
ZonedDateTime zdt = localdate.atStartOfDay(ZoneId.systemDefault());

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