+1 from me. Although I have fallen into Groovy's @Singleton vs Jakarta @Singleon pitfall, given that `java.time` classes are strongly recommended, I think this change is positive.
> On 31 May 2025, at 09:36, Paul King <pa...@asert.com.au> wrote: > > Hi folks, > > We have a feature request, and potential PR, to add java.time.* as a > new default import: > > https://issues.apache.org/jira/browse/GROOVY-11513 > https://github.com/apache/groovy/pull/2156 > > There are many good points about including such a star import but also > some drawbacks, so we'd like to gauge community feedback to understand > interest in having such a feature. > > First the good points: Groovy is known for allowing short scripts that > can do date manipulation, e.g. as one example: > > groovy -e "println 'Days left this year: ' + (365 - Calendar.instance[6])" > > Such one-liners become much longer if you have to do all the imports > which are required for the java.time classes even though they have > been the preferred ones to use for many years. > > Similarly, many domain classes in frameworks like Grails are often > composed from fields with simple types like strings, numbers, > booleans, and dates, or lists thereof. Many of these don't require > imports but java.time variants do. > > You may not write many one-liners or Grails domain classes, but > perhaps you write Gradle scripts. Again, many things don't need > imports but java.time classes would. > > So, having java.time imported automatically would be a good way to > promote the more robust java.time classes over the legacy equivalents > in a range of different scenarios. > > What are the downsides? > > Well, we have received feedback in the past that having too many > default imports can cause trouble. As just one example, there are > numerous frameworks/libraries that have a @Singleton annotation, and > the fact that Groovy's @Singleton is automatically imported is a cause > of temporary pain for folks that forget to import their framework's > version of that annotation. > > It is also a breaking change for anyone who has already created domain > classes in the default package that clash with the java.time classes. > This list includes the following classes: > > Clock > Duration > Instant > LocalDate > LocalDateTime > LocalTime > MonthDay > OffsetDateTime > OffsetTime > Period > Year > YearMonth > ZonedDateTime > ZoneId > ZoneOffset > DayOfWeek > Month > DateTimeException > > If folks have classes with those names in other packages, they are not > affected since existing imports in a source file are always before the > default ones. > > Let us know what you think. > > Cheers, Paul.