Error for formatting Cannot format given Object as a Date

Question

I have this code:

private static final SimpleDateFormat SIMPLE_DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");

Now, I try to format check some String data,

final String format = SIMPLE_DATE_FORMAT.format("2022-12-07T10:57:23.970Z");

I get the error that Cannot format the given Object as a Date. Whats the issue here and how do I resolve it?

Answer 1

There are two issues with your code snippet:

1. The format method formats a Date object to String. Perhaps, you want to use the parse method which will convert a String to a Date object.
2. The String you passed is not compliant with the pattern you passed. The Z in the pattern mandates that a timezone should be passed. A valid example would be -0700. An example of this is shown in the javadoc for SimpleDateFormat; just search with yyyy-MM-dd'T'HH:mm:ss.SSSZ.