public List<ReferenceType> definedClasses() {
   ArrayList<ReferenceType> definedClasses = new ArrayList<ReferenceType>();
   for (ReferenceType type : vm.allClasses()) {
     if (type.isPrepared() && equals(type.classLoader())) {
       definedClasses.add(type);
     }
   }
   return definedClasses;
 }