langSet.clear();
                        break;
                    }
                    final String normalizeLang = systemHelper.normalizeLang(lang);
                    if (normalizeLang != null) {
                        langSet.add(normalizeLang);
                    }
                }
            }
            if (!langSet.isEmpty()) {

                        langSet.add(Constants.ALL_LANGUAGES);
                    } else {
                        final String normalizeLang = systemHelper.normalizeLang(lang);
                        if (normalizeLang != null) {
                            langSet.add(normalizeLang);
                        }
                    }
                }
            }

            return defaultLang;
        }

        return normalizeLang(value);
    }

    /**
     * Normalizes a language string.
     *
     * @param value The language string to normalize.
     * @return The normalized language string.
     */
    public String normalizeLang(final String value) {
        if (StringUtil.isBlank(value)) {
            return null;
        }

    private final boolean normalizeKanji;
    private final boolean normalizeKana;

    public KuromojiIterationMarkCharFilterFactory(IndexSettings indexSettings, Environment env, String name, Settings settings) {
        super(indexSettings, name);
        normalizeKanji = settings.getAsBoolean("normalize_kanji", JapaneseIterationMarkCharFilter.NORMALIZE_KANJI_DEFAULT);