private static void findMissingLanguageModels(final String lngCode, final Consumer<List<Language>> consumer) {
        getDownloadedLanguageModels(availableLanguages -> {
            final List<Language> missingLanguages = new ArrayList<>();
            if (!availableLanguages.contains(lngCode)) {
                missingLanguages.add(new Language(lngCode));
            }
            final Language targetLanguage = Settings.getTranslationTargetLanguage();
            if (!availableLanguages.contains(targetLanguage.getCode())) {
                missingLanguages.add(targetLanguage);
            }
            consumer.accept(missingLanguages);
        });
    }
Checks if the language model for the source (from parameter) or target (from setting) language are missing
main/src/main/java/cgeo/geocaching/utils/OfflineTranslateUtils.java