NIFI-13579 Improve Timestamp Zone Offset Formatting and Parsing

[exceptionfactory]

Summary

NIFI-13579 Improves timestamp formatting and parsing for Record Readers and Record Writers as it relates to zone offset handling.

Following significant changes to move from java.util.Date to java.time classes for earlier 2.0.0 milestone releases, zone offset handling no longer worked in ways similar to earlier versions. When reading a timestamp string with a zone offset, LocalDateTime.parse() would ignore the zone offset and only consider the local date and time components. When writing a timestamp as a string, the converter would throw an exception due to the LocalDateTime object not having a value for offset seconds.

The current set of changes adjusts Field Converter behavior to address these issues. When converting from a string to a timestamp, the parsing makes use of the DateTimeFormatter.parseBest() method to first try parsing with ZonedDateTime to handle zone offsets, and then parsing with LocalDateTime.

When converting from a Timestamp or LocalDateTime to a string, the conversion creates a ZonedDateTime from a LocalDateTime using the system default zone offset, avoiding unexpected zone offset conversion.

Changes include new unit tests for these scenarios, as well as a new test for the ValidateRecord Processor with CSV Reader and Writer, exercising both sides of the conversion. These test methods get the current zone offset value from the JVM to ensure that tests work as expected regardless of the system timezone.

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  • JDK 21

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[dan-s1]

@exceptionfactory Changes look good and date is now formatted correctly in the submitter's case.
LGTM+1