[agentgt]

Yes CLOS is superior particularly multimethods.

As for the JVM: https://common-lisp.net/project/armedbear/

Sooo its not the JVM.

BTW AspectJ and JRebel will get you around methods and even inheritance changes but alas Java does not have multimethods or MOP. I mean CLOS is awesome but so is static analysis :)

[lispm]

ABCL implements CLOS classes in Java. It does not use the Java/JVM directly. For example a CLOS class is an instance of some Java class. This instance then has an attribute which has a vector of the CLOS slots. CLOS slots are not Java attributes themselves... The JVM object model is simply not able to provide CLOS features directly.

Last I've looked Jrebel used a funny mechanism. One couldn't just tell the class to add a slot, but one has to have Jrebel installed and given a new class file, it will detect it and then change/load the class...

That's a rather limited mechanism aimed at development... especially since it needs a license to work...