Re: Potential to include java.time.* as a default import for Groovy 5

The current proposal doesn't extend to the format and temporal
subpackages. With just the java.time classes and Groovy's datetime
extensions, you can go a long way. If you want all the bells and
whistles, then you'll need to import some classes/packages.

While it is outside the scope of this proposal, it would be
interesting to consider whether a custom type checker could be used
with CompileStatic to auto-import what looked like known classes.

Cheers, Paul.

On Mon, Jun 2, 2025 at 6:47 AM MG <mgbiz-yvYIh6MZAuFWk0Htik3J/[email protected]> wrote:
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> I think the idea is, that if the older java.util.Date family of classes gets auto-imported, then its newer counterpart should also be, which makes sense to me.
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> (As I understood it,  java.time.format & java.time.temporal would be auto-imported under the proposal (?))
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> I do however see the problem of where to draw the line with regards to other often used java.* packages (not related to the date-time domain).
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> Perhaps instead of auto importing more and more packages, Groovy could:
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> Issue a special kind of error if a script does not compile and it finds class names that match ones from well known / often used Java packages.
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> The error message could include the required import statements ready to copy into the script, if the user so chooses.
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> That would evidently not solve the "single line Groovy script" case, but how many people actually use Groovy that way... ?
> Single-line usage is always very limited in any case.
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> Support "compound imports", analogue to existing AnnotationCollector for annotations.
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> e.g.:
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> import all java // all but the most obscure Java libs
> import all java_core // all often used Java libs
> import all datetime // all DateTime related libs
> import all text // all text realted libs
> etc
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> Groovy then could come with some predefined "compound imports" like in the examples given above, as well as letting people define their own...
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> Cheers,
> mg
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> Am 01.06.2025 um 14:56 schrieb Alexander Veit via users:
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> Am 31.05.25 um 09:36 schrieb Paul King:
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> We have a feature request, and potential PR, to add java.time.* as a
> new default import:
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> https://issues.apache.org/jira/browse/GROOVY-11513
> https://github.com/apache/groovy/pull/2156
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> I would vote against this proposal. Here are some arguments why:
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> First of all, I'm generally not in favor of adding more default default imports to the language, since I suspect negative impacts on maintainability of scripts and the efficiency of the compilation process.
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> Apart from Instance, LocalDateTime and ZonedDateTime most of the classes in java.time are probably rarely used. Does this justify to add 16 extra classes?
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> The classes in java.time are not fully usable without classes from other packages like java.time.format or java.time.temporal which should then also be default imports.
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> There are many good points about including such a star import
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> This argument also holds for other packages like java.nio.* or java.text.
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