grails

Using G4 &amp; Java11, any reason why I wouldn't be seeing a `toCalendar()` method on `Timestamp` (i.e. derived from `java.sql.Date`)?

In Groovy 2.5 which is used in Grails 4 the date extensions were pulled out to a separate dependency.

Use the docs changing the URL to the version of G4 you are using to look up the Groovy version you are using:
<https://grails.github.io/legacy-grails-doc/4.0.0/guide/single.html#whatsNew>

Then go here and find that version for the date libraries:
<https://mvnrepository.com/artifact/org.codehaus.groovy/groovy-datetime>

For example, if you are on 4.0.0 in the docs it says it's using groovy 2.5.6 so you would add this dependency to your build:
implementation 'org.codehaus.groovy:groovy-datetime:2.5.6'

If I were you after you're done migrating to 4 I would upgrade to 5 which shouldn't be very difficult, and then be ready to upgrade whenever Grails 7 comes out.

Hm. I'm using Grails 4.1.4 == Groovy 2.5.14 == groovy-datetime:2.5.14 which I've tried adding to both the elasticsearch-plugin .jar build as well as my project build and groovy-datetime dependency is showing as loaded but it doesn't seem to be plugging that `toCalendar()` method. Doesn't appear to be having any runtime effect at all...