I would say that yes, on paper you can: I haven't tried directly but remember that Groovy is one of the very few languages to retain a seamless integration with the Java Runtime Platform: it runs inside the JVM and makes use
of Java’s libraries (JRE). Groovy is only
a new way of creating ordinary Java classes —
from a runtime perspective, Groovy is Java
with an additional JAR file as a dependency.
Thus you can write a Java wrapper for the groovy classes onto which Inline::Java can plug in.
That said: Groovy is a sort of Perl for the JVM, it's pretty powerful/feature rich, unless you have already a vast of Perl 5 code which need the Groovy script/program functionality, I'd recommend stick with it: it also supports so-called "slashy" // regular expression literals (I'll let you guess where they have "stolen" the idea) among loads of other very nice feats.