code: private boolean isModelClass(String classname, Bundle bundle) {
          LOGGER.debug("Check if class '{}' is a model class", classname);
          Class<?> clazz;
          try {
              clazz = bundle.loadClass(classname);
          } catch (ClassNotFoundException e) {
              LOGGER.warn("Bundle could not load its own class: '{}' bundle: '{}'", classname, bundle.getSymbolicName());
              LOGGER.debug("Exact error: ", e);
              return false;
          } catch (NoClassDefFoundError e) {
              // ignore since this happens if bundle have optional imports
              return false;
          } catch (Error e) {
              // if this catch clause is reached, then the bundle which caused this error need to be checked. There
              // is something wrong with the setup of the bundle (e.g. double import of a library of different versions)
              LOGGER.warn("Error while loading class: '{}' in bundle: '{}'", classname, bundle.getSymbolicName());
              LOGGER.debug("Exact error: ", e);
              return false;
          }
          return clazz.isAnnotationPresent(Model.class);
      }
docs: Returns true if the class with the given class name contained in the given bundle is a model and false if not or
  the class couldn't be loaded.