code: public static void checkDeclaringClassLoadable(Class<?> c) {
          for (Class<?> clazz = c; clazz != null; clazz = clazz.getDeclaringClass()) {
              // noop, the loop triggers loading of the declaring classes
          }
      }
docs: Triggers loading of declaring class (if any) of the given class recursively.
  If the class cannot be loaded, the underlying {@link LinkageError} is propagated.
  @param class the given class
  @throws LinkageError or its subclass if a declaring class cannot be loaded