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DateTimeParseException: Text '2020-04-01T08:53:47.000+02:00 00:00' could not be parsed, unparsed text found at index 29

Getting a DateTimeParseExcpetion when trying to convert the String 2020-04-01T08:53:47.000+02:00 00:00
String date = "2020-04-01T08:53:47.000+02:00 00:00";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSz");
parsedDate = LocalDateTime.parse(date,formatter).toString();
System.out.println(parsedDate);

Your pattern is not the same as your String. Check the last part where is 000+02:00 00:00.
Your pattern is: SSSz
If you try this:
String date = "2020-04-01T08:53:47.000";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS");
It will works because your date is like your pattern. Note that every number in the date is into pattern too.
But for your date there is an empty space what no make sense, so removing it, the code works perfectly.
String date = "2020-04-01T08:53:47.000+02:00";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSz");
Output:
2020-04-01T08:53:47
Note that z is the local time and means "zero hour offset" or "Zulu time" (UTC) and you can use Locale.

The 00:00 at the end of your date-time string doesn't make sense to me. Parse the date-time string after stripping that.
import java.time.LocalDateTime;
import java.time.OffsetDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
public class Main {
public static void main(String[] args) {
String strDate = "2020-04-01T08:53:47.000+02:00 00:00";
strDate = strDate.substring(0, strDate.lastIndexOf(' '));
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd'T'HH:mm:ss.SSSz", Locale.ENGLISH);
LocalDateTime parsedDate = LocalDateTime.parse(strDate, formatter);
System.out.println(parsedDate);
OffsetDateTime odt = OffsetDateTime.parse(strDate);
System.out.println(odt);
System.out.println(odt.getOffset());
}
}
Output:
2020-04-01T08:53:47
2020-04-01T08:53:47+02:00
+02:00
Note: You can parse your date-time string (after striping 00:00 from the end of it) to OffsetDateTime in order to preserve the zone-offset information.

Use the built-in formatter
The built-in DateTimeFormatter.ISO_OFFSET_DATE_TIME matches the part of your string that we can understand. And it can parse just that part and ignore the rest.
String date = "2020-04-01T08:53:47.000+02:00 00:00";
ParsePosition pp = new ParsePosition(0);
OffsetDateTime odt = OffsetDateTime.from(
DateTimeFormatter.ISO_OFFSET_DATE_TIME.parse(date, pp));
System.out.println("Date and time: " + odt);
System.out.println("Unparsed text: " + date.substring(pp.getIndex()));
Output:
Date and time: 2020-04-01T08:53:47+02:00
Unparsed text: 00:00
Since your string contains an offset from UTC, OffsetDateTime is the correct class to parse into. If we used LocalDateTIme, the offset would be ignored, and we would end up not knowing at which offset the time was to be interpreted, that is, we could not know which point in time it was. With OffsetDateTime the point in time is unambiguous. If you want to convert to the time in your own time zone, convert to ZonedDateTime (still not LocalDateTime).
ZonedDateTime timeInMyTimeZone = odt.atZoneSameInstant(ZoneId.systemDefault());
System.out.println("Date and time: " + timeInMyTimeZone);
Example output:
Date and time: 2020-04-01T11:53:47+05:00[Asia/Aqtobe]
Links
Documentation links:
DateTimeFormatter.ISO_OFFSET_DATE_TIME.
The two-arg DateTimeFormatter.parse​(CharSequence, ParsePosition) that I used.

Java 8 DateTimeFormatter to ignore millisecond and zone

I am struggling with Java 8 DateTimeFormatter.
I would like to convert a given String to dateFormat and parse to LocalDateTime
Here is my code
DateTimeFormatter f = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss")
String text = "2020-01-01T01:01:11.123Z"
LocalDateTime date = LocalDateTime.parse(text, f)
But Java throws
Text could not be parsed, unparsed text found at index 19
If I change ofPattern to yyyy-MM-dd'T'HH:mm:ss.SSSX, my code executes without any error.
But I don’t want to use millisecond and time zone.

Do this instead:
String text = "2020-01-01T01:01:11.123Z";
LocalDateTime date = ZonedDateTime.parse(text)
.toLocalDateTime();
To get rid of the milliseconds information, do:
LocalDateTime date = ZonedDateTime.parse(text)
.truncatedTo(ChronoUnit.SECONDS)
.toLocalDateTime();
You can also use OffsetDateTime in place of ZonedDateTime.

Reformatting a Date from DD-MMM-YYYY to YYYYDDMM or YYYYMMDD

I'm trying to use Java 8 to re-format today's date but I'm getting the following error:
java.time.format.DateTimeParseException: Text '09-OCT-2017' could not be parsed:
Unable to obtain LocalDate from TemporalAccessor:
{WeekBasedYear[WeekFields[SUNDAY,1]]=2017, MonthOfYear=10, DayOfYear=9},ISO of type java.time.format.Parsed
Code:
public static String formatDate(String inputDate, String inputDateFormat, String returnDateFormat){
try {
DateTimeFormatter inputFormatter = new DateTimeFormatterBuilder().parseCaseInsensitive().appendPattern(inputDateFormat).toFormatter(Locale.ENGLISH);
LocalDate localDate = LocalDate.parse(inputDate, inputFormatter);
DateTimeFormatter outputFormatter = DateTimeFormatter.ofPattern(returnDateFormat);
String formattedString = localDate.format(outputFormatter);
return formattedString;
} catch (DateTimeParseException dtpe) {
log.error("A DateTimeParseException exception occured parsing the inputDate : " + inputDate + " and converting it to a " + returnDateFormat + " format. Exception is : " + dtpe);
}
return null;
}
I previously tried using SimpleDateFormat, but the problem is my inputDateFormat format is always in uppercase DD-MMM-YYYY, which was giving me incorrect results, so I tried using parseCaseInsensitive() to ignore the case sensitivity.

In the comments you told that the input format is DD-MMM-YYYY. According to javadoc, uppercase DD is the day of year field, and YYYY is the week based year field (which might be different from the year field).
You need to change them to lowercase dd (day of month) and yyyy (year of era). The parseCaseInsensitive() only takes care of the text fields - in this case, the month name (numbers are not affected by the case sensitivity - just because the month is in uppercase, it doesn't mean that the numbers patterns should also be).
The rest of the code is correct. Example (changing the format to yyyyMMdd):
String inputDate = "09-OCT-2017";
DateTimeFormatter inputFormatter = new DateTimeFormatterBuilder()
.parseCaseInsensitive()
// use "dd" for day of month and "yyyy" for year
.appendPattern("dd-MMM-yyyy")
.toFormatter(Locale.ENGLISH);
LocalDate localDate = LocalDate.parse(inputDate, inputFormatter);
// use "dd" for day of month and "yyyy" for year
DateTimeFormatter outputFormatter = DateTimeFormatter.ofPattern("yyyyMMdd");
String formattedString = localDate.format(outputFormatter);
System.out.println(formattedString); // 20171009
The output of the code above is:
20171009
Regarding your other comment about not having control over the input pattern, one alternative is to manually replace the letters to their lowercase version:
String pattern = "DD-MMM-YYYY";
DateTimeFormatter inputFormatter = new DateTimeFormatterBuilder()
.parseCaseInsensitive()
// replace DD and YYYY with the lowercase versions
.appendPattern(pattern.replace("DD", "dd").replaceAll("YYYY", "yyyy"))
.toFormatter(Locale.ENGLISH);
// do the same for output format if needed
I don't think it needs a complex-replace-everything-in-one-step regex. Just calling the replace method multiple times can do the trick (unless you have really complex patterns that would require lots of different and complex calls to replace, but with only the cases you provided, that'll be enough).

I hope I got you right.
Formatting a String to LocalDate is acutally pretty simple. Your date format is that here right 09-Oct-2017?
Now you just need use the split command to divide that into a day, month and year:
String[] tempStr = inputDate.split("-");
int year = Integer.parseInt(tempStr[2]);
int month = Integer.parseInt(tempStr[1]);
int day = Integer.parseInt(tempStr[0]);
After that it´s pretty easy to get that to LocalDate:
LocalDate ld = LocalDate.of(year, month, day);
I hope that helps.

How to remove milliseconds from LocalTime in java 8

Using the java.time framework, I want to print time in format hh:mm:ss, but LocalTime.now() gives the time in the format hh:mm:ss,nnn. I tried to use DateTimeFormatter:
DateTimeFormatter formatter = DateTimeFormatter.ISO_LOCAL_TIME;
LocalTime time = LocalTime.now();
String f = formatter.format(time);
System.out.println(f);
The result:
22:53:51.894
How can I remove milliseconds from the time?

Edit: I should add that these are nanoseconds not milliseconds.
I feel these answers don't really answer the question using the Java 8 SE Date and Time API as intended. I believe the truncatedTo method is the solution here.
LocalDateTime now = LocalDateTime.now();
System.out.println("Pre-Truncate: " + now);
DateTimeFormatter dtf = DateTimeFormatter.ISO_DATE_TIME;
System.out.println("Post-Truncate: " + now.truncatedTo(ChronoUnit.SECONDS).format(dtf));
Output:
Pre-Truncate: 2015-10-07T16:40:58.349
Post-Truncate: 2015-10-07T16:40:58
Alternatively, if using Time Zones:
LocalDateTime now = LocalDateTime.now();
ZonedDateTime zoned = now.atZone(ZoneId.of("America/Denver"));
System.out.println("Pre-Truncate: " + zoned);
DateTimeFormatter dtf = DateTimeFormatter.ISO_OFFSET_DATE_TIME;
System.out.println("Post-Truncate: " + zoned.truncatedTo(ChronoUnit.SECONDS).format(dtf));
Output:
Pre-Truncate: 2015-10-07T16:38:53.900-06:00[America/Denver]
Post-Truncate: 2015-10-07T16:38:53-06:00

cut to minutes:
localTime.truncatedTo(ChronoUnit.MINUTES);
cut to seconds:
localTime.truncatedTo(ChronoUnit.SECONDS);
Example:
import java.time.LocalTime;
import java.time.temporal.ChronoUnit;
LocalTime.now()
.truncatedTo(ChronoUnit.SECONDS)
.format(DateTimeFormatter.ISO_LOCAL_TIME);
Outputs 15:07:25

Just create the DateTimeFormatter explicitly:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss", Locale.US);
LocalTime time = LocalTime.now();
String f = formatter.format(time);
System.out.println(f);
(I prefer to explicitly use the US locale, to make it clear that I don't want anything from the default format locale.)

Use this in your first line
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss");

Try to use patterns defined here: http://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html
For example:
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy MM dd HH. mm. ss");
String text = date.toString(formatter);

You can so it simply by using regex on the string:
String f = formatter.format(time).replaceAll("\\.[^.]*", "");
This deletes (by replacing with blank) the last dot and everything after.

Calendar date to yyyy-MM-dd format in java

How to convert calendar date to yyyy-MM-dd format.
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, 1);
Date date = cal.getTime();
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");
String date1 = format1.format(date);
Date inActiveDate = null;
try {
inActiveDate = format1.parse(date1);
} catch (ParseException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
This will produce inActiveDate = Wed Sep 26 00:00:00 IST 2012. But what I need is 2012-09-26. My purpose is to compare this date with another date in my database using Hibernate criteria. So I need the date object in yyyy-MM-dd format.

A Java Date is a container for the number of milliseconds since January 1, 1970, 00:00:00 GMT.
When you use something like System.out.println(date), Java uses Date.toString() to print the contents.
The only way to change it is to override Date and provide your own implementation of Date.toString(). Now before you fire up your IDE and try this, I wouldn't; it will only complicate matters. You are better off formatting the date to the format you want to use (or display).
Java 8+
LocalDateTime ldt = LocalDateTime.now().plusDays(1);
DateTimeFormatter formmat1 = DateTimeFormatter.ofPattern("yyyy-MM-dd", Locale.ENGLISH);
System.out.println(ldt);
// Output "2018-05-12T17:21:53.658"
String formatter = formmat1.format(ldt);
System.out.println(formatter);
// 2018-05-12
Prior to Java 8
You should be making use of the ThreeTen Backport
The following is maintained for historical purposes (as the original answer)
What you can do, is format the date.
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, 1);
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");
System.out.println(cal.getTime());
// Output "Wed Sep 26 14:23:28 EST 2012"
String formatted = format1.format(cal.getTime());
System.out.println(formatted);
// Output "2012-09-26"
System.out.println(format1.parse(formatted));
// Output "Wed Sep 26 00:00:00 EST 2012"
These are actually the same date, represented differently.

Your code is wrong. No point of parsing date and keep that as Date object.
You can format the calender date object when you want to display and keep that as a string.
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, 1);
Date date = cal.getTime();
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");
String inActiveDate = null;
try {
inActiveDate = format1.format(date);
System.out.println(inActiveDate );
} catch (ParseException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

java.time
The answer by MadProgrammer is correct, especially the tip about Joda-Time. The successor to Joda-Time is now built into Java 8 as the new java.time package. Here's example code in Java 8.
When working with date-time (as opposed to local date), the time zone in critical. The day-of-month depends on the time zone. For example, the India time zone is +05:30 (five and a half hours ahead of UTC), while France is only one hour ahead. So a moment in a new day in India has one date while the same moment in France has “yesterday’s” date. Creating string output lacking any time zone or offset information is creating ambiguity. You asked for YYYY-MM-DD output so I provided, but I don't recommend it. Instead of ISO_LOCAL_DATE I would have used ISO_DATE to get this output: 2014-02-25+05:30
ZoneId zoneId = ZoneId.of( "Asia/Kolkata" );
ZonedDateTime zonedDateTime = ZonedDateTime.now( zoneId );
DateTimeFormatter formatterOutput = DateTimeFormatter.ISO_LOCAL_DATE; // Caution: The "LOCAL" part means we are losing time zone information, creating ambiguity.
String output = formatterOutput.format( zonedDateTime );
Dump to console…
System.out.println( "zonedDateTime: " + zonedDateTime );
System.out.println( "output: " + output );
When run…
zonedDateTime: 2014-02-25T14:22:20.919+05:30[Asia/Kolkata]
output: 2014-02-25
Joda-Time
Similar code using the Joda-Time library, the precursor to java.time.
DateTimeZone zone = new DateTimeZone( "Asia/Kolkata" );
DateTime dateTime = DateTime.now( zone );
DateTimeFormatter formatter = ISODateTimeFormat.date();
String output = formatter.print( dateTime );
ISO 8601
By the way, that format of your input string is a standard format, one of several handy date-time string formats defined by ISO 8601.
Both Joda-Time and java.time use ISO 8601 formats by default when parsing and generating string representations of various date-time values.

java.util.Date object can't represent date in custom format instead you've to use SimpleDateFormat.format method that returns string.
String myString=format1.format(date);

public static void main(String[] args) {
Calendar cal = Calendar.getInstance();
cal.set(year, month, date);
SimpleDateFormat format1 = new SimpleDateFormat("yyyy MM dd");
String formatted = format1.format(cal.getTime());
System.out.println(formatted);
}

In order to parse a java.util.Date object you have to convert it to String first using your own format.
inActiveDate = format1.parse( format1.format(date) );
But I believe you are being redundant here.

Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, 7);
Date date = c.getTime();
SimpleDateFormat ft = new SimpleDateFormat("MM-dd-YYYY");
JOptionPane.showMessageDialog(null, ft.format(date));
This will display your date + 7 days in month, day and year format in a JOption window pane.

public static String ThisWeekStartDate(WebDriver driver) {
Calendar c = Calendar.getInstance();
//ensure the method works within current month
c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
System.out.println("Before Start Date " + c.getTime());
Date date = c.getTime();
SimpleDateFormat dfDate = new SimpleDateFormat("dd MMM yyyy hh.mm a");
String CurrentDate = dfDate.format(date);
System.out.println("Start Date " + CurrentDate);
return CurrentDate;
}
public static String ThisWeekEndDate(WebDriver driver) {
Calendar c = Calendar.getInstance();
//ensure the method works within current month
c.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
System.out.println("Before End Date " + c.getTime());
Date date = c.getTime();
SimpleDateFormat dfDate = new SimpleDateFormat("dd MMM yyyy hh.mm a");
String CurrentDate = dfDate.format(date);
System.out.println("End Date " + CurrentDate);
return CurrentDate;
}

I found this code where date is compared in a format to compare with date field in database...may be this might be helpful to you...
When you convert the string to date using simpledateformat, it is hard to compare with the Date field in mysql databases.
So convert the java string date in the format using select STR_to_DATE('yourdate','%m/%d/%Y') --> in this format, then you will get the exact date format of mysql date field.
http://javainfinite.com/java/java-convert-string-to-date-and-compare/

My answer is for kotlin language.
You can use SimpleDateFormat to achieve the result:
val date = Date(timeInSec)
val formattedDate = SimpleDateFormat("yyyy-MM-dd", Locale("IN")).format(date)
for details click here.
OR
Use Calendar to do it for you:
val dateObject = Date(timeInMillis)
val calendarInstance = Calendar.getInstance()
calendarInstance.time = dateObject
val date = "${calendarInstance.get(Calendar.YEAR)}-${calendarInstance.get(Calendar.MONTH)}-${calendarInstance.get(Calendar.DATE)}"
For more details check this answer.

I don't know about y'all, but I always want this stuff as a one-liner. The other answers are fine and dandy and work great, but here is it condensed to a single line. Now you can hold less lines of code in your mind :-).
Here is the one Liner:
String currentDate = new SimpleDateFormat("yyyy-MM-dd").format(new Date());