Do note that the FastDateFormat et al. classes are copied directly from Apache Commons. Most changes done there are relevant to upstream. :)
On Fri, 7 May 2021 at 10:14, Volkan Yazıcı <volkan.yaz...@gmail.com> wrote: > > Hello, > > I am trying to tackle LOG4J2-3075 > <https://issues.apache.org/jira/browse/LOG4J2-3075> reporting that > JsonTemplateLayout doesn't format nanoseconds. I have done some preliminary > study and checked *DatePatternConverter* for inspiration. In a nutshell, > this is what *DataPatternConverter* does: > > private Formatter createFormatter(final String[] options) { > final FixedDateFormat fixedDateFormat = > FixedDateFormat.createIfSupported(options); > if (fixedDateFormat != null) { > return createFixedFormatter(fixedDateFormat); > } > return createNonFixedFormatter(options); > } > > If *FixedDateFormat* supports the user pattern, it uses the > *FixedDateFormat*, otherwise it falls back to *FastDateFormat*. Here comes > the tricky part... *FixedDateFormat#formatInstant()* supports nanoseconds > passed in by the Log4j *Instant* argument. Though *FastDateFormat* doesn't > format nanoseconds at all. Hence, if the user pattern is not supported by > the *FixedDateFormat*, the fallback *FastDateFormat* doesn't support > nanoseconds. The solution I have in mind is to extend *FastDateFormat* to > support nanoseconds. This is not easy either: *FastDateFormat* accepts Java > *Calendar*, which doesn't support. The not-so-good-but-okayish solution is > to add a similar *#formatInstant()* method to *FastDateFormat*. What do you > think? > > Kind regards.
