code: @SuppressWarnings("unchecked")
      public List<Class<Object>> getItems(final Predicate<ItemInfo> filter) {
          final List<Class<Object>> items = (List) Lists.newArrayList(itemsHolder.values());
          return filter(items, filter);
      }
docs: Used to query items of all configuration types. May be useful to build configuration tree (e.g. to search
  all items configured by bundle or by classpath scan). Some common filters are
  predefined in {@link Filters}. Use {@link Predicate#and(Predicate)}, {@link Predicate#or(Predicate)}
  and {@link Predicate#negate()} to reuse default filters.
  <p>
  Pay attention that disabled (or disabled and never registered) items are also returned.
  
  @param filter predicate to filter definitions
  @return registered item classes in registration order, filtered with provided filter or empty list