public class LocaleLanguage {
    public static Language DEFAULT = Language.RU;
    private static final EnumMap<Language, Map<String, Object>> languageMap = new EnumMap<>(Language.class);
    private final ClassLoader loader;

    public LocaleLanguage(ClassLoader loader) {
        this.loader = loader;
    }

    public Map<String, Object> load(Language lang) {
        return languageMap.compute(lang, (language, map) -> {
            try (InputStream stream = loader.getResourceAsStream(lang.getFileName() + ".json")) {
                assert stream != null;
                try (InputStreamReader inputStreamReader = new InputStreamReader(stream, StandardCharsets.UTF_8)) {
                    Map<String, Object> mapFromJson = StringBind.GSON.fromJson(inputStreamReader, new LocalizationTypeToken().getType());
                    if(map == null) {
                        map = mapFromJson;
                    } else {
                        map.putAll(mapFromJson);
                    }
                }
            } catch (IOException e) {
                throw new RuntimeException(e);//todo: ошибка
            }
            return map;
        });
    }
    private Map<String, Object> getOrLoad(Language lang) {
        return languageMap.putIfAbsent(lang, load(lang));
    }
    public String getCorrectLine(Language lang, String key, Object... args) {
        return String.format(getOrLoad(lang).get(key).toString(), args);
    }

    public Object get(Language lang, String key) {
        Object value = getOrLoad(lang).get(key);
        return value != null ? value : key;
    }
    private static class LocalizationTypeToken extends TypeToken<Map<String, Object>> {
        private static final long serialVersionUID = 3988518176787768044L;
    }
}