Must qualify the allocation with an enclosing instance of type GameTree (e.g. x.new A () where x is an instance of GameTree). GameTree.java line 146</pre> ...

The syntax Calendar.metaClass.getZodiakTropicalSign = { -> defines a new method getZodiakTrpopicalSign on Calendar and then uses delegate to work with the underlying instance of java.util.Calendar.

Developers who create a runnable Java class, be it for a ‘Hello World’ demonstration or to kick off a fully featured enterprise application, will enjoy the following technical benefits when using ...

It can now be used to annotate an explicit accessor method in a record. The Java 14 Feature Spotlight:Records, written by Brian Goetz, provides some more details and examples for records.