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I'm using SimpleDateFormat to parse a string containing a date/time, but the result has a different date, hour, minute, second and millisecond: SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM...
#1: Initial revision
by
hkotsubo
·
2021-08-20T16:22:44Z (over 2 years ago)
How to parse a date with more than 3 decimal digits in the fractions of second?
I'm using `SimpleDateFormat` to parse a string containing a date/time, but the result has a different date, hour, minute, second and millisecond:
```java
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSSSSSSS");
Date date = sdf.parse("2021-10-01T10:30:45.123456789");
System.out.println(date); // Sat Oct 02 20:48:21 BRT 2021
// get the millisecond value
Calendar cal = Calendar.getInstance();
cal.setTime(date);
System.out.println(cal.get(Calendar.MILLISECOND)); // 789
```
As you can see, the input date is October 1<sup>st</sup> 2021, at 10:30:45 AM, but the output date is October **2<sup>nd</sup>** 2021, at **8:48:21 PM**. As printing a `Date` uses its `toString()` method, and it doesn't show the milliseconds, I've used a `Calendar` to get this value: I expected it to be `123`, but it was `789`.
I noticed that it happens only when the fraction of seconds has more than 3 decimal digits (with 3 or less digits, it works). But I need to parse dates with up to 9 decimal digits, so how can I do it? And why is `SimpleDateFormat` changing the date/time values?