code: private void buildMap(List<CLDR.Locale> availableBundles) {
      // Index all bundles by their original bundle identifier and the maximum
      // bundle identifier.
      List<MetaLocale> maxBundleIds = new ArrayList<>();
      for (CLDR.Locale locale : availableBundles) {
        MetaLocale source = (MetaLocale) locale;
        if (source.isRoot()) {
          continue;
        }
        
        MetaLocale maxBundleId = languageResolver.addLikelySubtags(source);
        maxBundleIds.add(maxBundleId);
        availableBundlesMap.put(source.copy(), source); 
        if (!source.equals(maxBundleId)) {
          availableBundlesMap.putIfAbsent(maxBundleId.copy(), source);
        }
      }
      
      // Iterate over the maximum bundle identifiers, indexing the permutations
      // generated by our matching order.
      for (MetaLocale bundleId : maxBundleIds) {
        indexPermutations(bundleId);
      }
    }
docs: Iterate over the available bundle identifiers, expand them and index all
  permutations to enable a fast direct lookup.