On the 3rd run (= 2nd incremental update), FromNode.resultClass's ClassLoader is old so the list element objects don't match the resultClass.

Why this happens on the 3rd run? Because

• The 1st run : KnowledgePackageImpl doesn't have typeResolver.
• The 2nd run : KieBaseUpdaterImpl lets KnowledgePackageImpl create a ClassTypeResolver which caches classes in cachedImports.
• The 3rd run : KieBaseUpdaterImpl reuses the KnowledgeBaseImpl, KnowledgePackageImpl and the ClassTypeResolver.

TypeResolver.cachedImports may return a Class with an old ClassLoader but KieBaseUpdaterImpl calls kbuilder.rewireAllClassObjectTypes() to solve the classloader mismatch. The problem is that FromNode holds resultClass as a bare Class object which is not reached by wiring.