[jbosscache-dev] Immutables.immutableSetCopy

This method looks quite inefficient for its actual usage. A look in the IDE shows its used by UnversionedNode.getChildrenNames() and getKeysDirect(). Those pass either a ConcurrentHashMap$KeySet, a FastCopyHashMap$KeySet, Collections$EmptySet or Collections$SingletonSet. The attempted optimizations (some of which involve reflection) in immutableSetCopy can handle non of those and eventually the HashSet copy constructor gets called. A profiling run showed 22 invocations of UnversionedNode.getKeysDirect() took 3,804 microseconds, of which 3,563 was in immutableSetCopy. 789 of that was in the new HashSet(toCopy) call; the rest was basically wasted. Any reason I shouldn't just turn this into a new HashSet(toCopy) call? -- Brian Stansberry Lead, AS Clustering JBoss by Red Hat