java:call

(java:call object "methodName" args...)

Invokes an instance method on a java object by reflection, choosing the overload whose parameters best match the arguments, and returns the marshalled result (a void method returns nil). Part of the JVM-only java interop package — available on the interpreter and in JVM-compiled classes, not on the WASM backend. See the Java interop guide.

A java.util.ArrayList is created, one element is added, and size returns the element count.