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java.time.format.DateTimeParseException: Text '10-03-2021' could not be parsed at index 0

I am trying to convert a string to date format with Java8 using DateTimeFormatter in spring boot, But I receive an error [[java.time.format.DateTimeParseException: Text '10-03-2021' could not be parsed at index 0]]. I am using LocalDate because I want my output to have only date without time. What Am I doing wrong in my code.
String date= "10-03-2021"
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("EEEE, MMM d, yyyy",Locale.forLanguageTag("sw-TZ"));
LocalDateTime dateTime = LocalDateTime.parse(date, formatter);
System.out.println(dateTime.format(formatter));

You need to parse date in dd-MM-yyyy pattern first and then format it to the pattern of your choice.
String date= "10-03-2021";
DateTimeFormatter format = DateTimeFormatter.ofPattern("dd-MM-yyyy");
LocalDate localDate = LocalDate.parse(date, format);
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("EEEE, MMM d, yyyy",Locale.forLanguageTag("sw-TZ"));
System.out.println(localDate.format(formatter));

DateFormat from ''yyyy-MM-dd" to "dd-MM" using Joda-Time

I have following code:
DateTimeFormatter dtf = DateTimeFormat.forPattern("dd/MM");
LocalDate weekMon = new LocalDate().withWeekOfWeekyear(thisWeek).withDayOfWeek(DateTimeConstants.MONDAY);
System.out.println(weekMon.toString());
LocalDate weekFin = dtf.parseLocalDate(weekMon.toString());
and the output prints the date correctly: 2015-02-02. I'm trying to convert it to European format and ignoring the year as "dd-MM" -> "02-02" but the line:
LocalDate weekFin = dtf.parseLocalDate(weekMon.toString());
keeps throwing following exception:
java.lang.IllegalArgumentException: Invalid format: "2015-02-02" is malformed at "5-02-02"
What is wrong with the formation in this case ?.

Probably what you need is to print, and not to parse.
In other words:
String dateStr = dtf.print(weekMon);
Notice that with this code:
LocalDate weekFin = dtf.parseLocalDate(weekMon.toString());
you are trying to parse a string in "yyyy-MM-dd" format using a formatter that accepts strings in "dd/MM" format. Hence the exception...

Joda time convert query

How to convert from "2014-06-16T07:00:00.000Z" to "16-JUN-14 07:00:00" using joda time API?
The below code is throwing the exception
java.lang.IllegalArgumentException: Illegal pattern component: T
at org.joda.time.format.DateTimeFormat.parsePatternTo(DateTimeFormat.java:570)
at org.joda.time.format.DateTimeFormat.createFormatterForPattern(DateTimeFormat.java:693)
at org.joda.time.format.DateTimeFormat.forPattern(DateTimeFormat.java:181)
at com.joda.JodaTimeTest.convertJodaTimezone(JodaTimeTest.java:59)
at com.joda.JodaTimeTest.main(JodaTimeTest.java:50)
This is the code:
DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-ddTHH:mm:ssZ");
DateTime dt = formatter.parseDateTime(dstDateTime.toString());

You need to enclose the literal T within single quotes. Also the milliseconds are not properly patterned. You need to include SSS for the milliseconds. Have a look at the patterns here for more info.
DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
Update: To format the DateTime into a String representation of your choice, you need to do this.
DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
DateTime dt = formatter.parseDateTime(dstDateTime.toString()); // You get a DateTime object
// Create a new formatter with the pattern you want
DateTimeFormatter formatter2 = DateTimeFormat.forPattern("dd-MMM-yy HH:mm:ss");
String dateStringInYourFormat = formatter2.print(dt); // format the DateTime to that pattern
System.out.println(dateStringInYourFormat); // Prints 16-Jun-14 12:30:00 because of the TimeZone I'm in
Either specify the timezone yourself or your default system timezone would be taken.

You need to change
"yyyy-MM-ddTHH:mm:ssZ"
To
"yyyy-MM-dd'T'HH:mm:ss.SSS'Z"
Now
DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'Z");
DateTime dt = formatter.parseDateTime("2014-06-16T07:00:00.000Z");
System.out.println(dt);
Output:
2014-06-16T07:00:00.000+05:30

Easiest way to parse date in String format to GregorianCalendar

I have the following date:
2011-10-07T08:51:52.006Z
Now I want to parse it into a GregorianCalendar. Is there an easier way to do it than using substrings and parsing them to Integers?
And what is the Z in the time string?
I tried to parse it using SimpleDateFormat, but I can´t find a explanation for the T in the date String.

DateFormat format = new SimpleDateFormat( "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'" )
Date date = format.parse( "2011-10-07T08:51:52.006Z" );
Calendar calendar = new GregorianCalendar();
calendar.setTime( date );

I would take a look at DateTimeFormatter
DateTimeFormatter formatter =
DateTimeFormat.forPattern("<custom_pattern>").withOffsetParsed();
DateTime dateTime = formatter.parseDateTime("<your_input>");
GregorianCalendar cal = dateTime.toGregorianCalendar();
The T in your string acts as a separator between the date and the time and the Z is the time-zone information both as per ISO-8601 format.

You could use the SimpleDateFormatter to parse the String. Please read the javadoc for the aforementioned class to know what could be the format string. 'Z' indicates the timezone information.

Fail to parse date with time zone with Joda Time

I am trying to use Joda Time both for formatting DateTime objects to String and than parse these strings back to DateTime. But I am failing to so when the pattern includes z:
DateTimeFormatter dtf = DateTimeFormat.forPattern("dd-MM-yyyy HH:mm:ss.SSS z");
String dts = dtf.print(System.currentTimeMillis());
System.out.println(dts);
DateTime dt = dtf.parseDateTime(dts);
The above code is throwing exception when the parsing the String to DateTime takes occurred.
Do you have any idea?
Yosi

You can do:
DateTime dt = new DateTime();
System.out.println(dt.toString("dd-MM-yyyy HH:mm:ss.SSS z"));
Have a look in the user guide

The Pattern is not correct, maybe try this one
DateTimeFormatter dtf = DateTimeFormat.forPattern( "dd-MM-yyyy HH:mm:ss.SSS'z" );
this worked for me