That sure sounds like an oversight to me. The return type would have to ArrayList, which is a bit odd for the uninitiated, but that doesn't seem like a reason not to return values.
Side note: ArrayList??? Seems we should consider changing HAPartition.callMethodOnCluster to return List.
OK - I'll initially modify HAServiceMBeanSupport.callMethodOnPartition() to return an ArrayList. That shouldn't break any existing code and will make the RPC results available to interested clients.
I agree that it would be preferable to have HACluster.callMethodOnCluster() return a List. Changing this will break callers in the cluster module and possibly in another module or two. Of course, it will also break any client code which utilizes this RPC support.
I won't make this change unless we decide to proceed but I'll take a quick look at the effect on JBoss code.
I modified HAServiceMBeanSupport.callMethodOnPartition() to return a List. If we subsequently modify HAPartition to do the same, we won't need to revisit this implementation. See JBAS-4560 for details.