private void addMetaTypeProviderWrappers(
     String servicePropertyName,
     ServiceReference<Object> serviceReference,
     MetaTypeProvider service,
     boolean factory,
     Set<MetaTypeProviderWrapper> wrappers) {
   String[] pids =
       getStringProperty(servicePropertyName, serviceReference.getProperty(servicePropertyName));
   for (String pid : pids) {
     wrappers.add(new MetaTypeProviderWrapper(service, pid, factory));
   }
 }