ParseCountry.java

    /**
     * This method extracts the country information from the parsed lines. We first check if COUNTRY is present in the
     * provided map. If not, we check if LOCALE is present.
     * <br><br>
     * In the case of LOCALE we process the string and try to extract the country code from it.
     *
     * @param values The values parsed from the list of lines.
     *
     * @return The Optional country object, which is present of if the values map contains COUNTRY or LOCALE key.
     */
    private static Optional<Country> parseCountry(final Map<Attribute, List<String>> values) {
        // Our default matcher is to not select anything.
        Predicate<Country> matcher = c -> Boolean.FALSE;

        if (values.containsKey(Attribute.COUNTRY)) {
            // We use the country key as matcher
            matcher = c -> c.getKey().equalsIgnoreCase(values.get(Attribute.COUNTRY).get(0));
        } else if (values.containsKey(Attribute.LOCALE)) {
            // We process the locale key and then match it against the country key.
            final String[] value = values.get(Attribute.LOCALE).get(0).split("_|-");

            matcher = c -> value.length == 2 && c.getKey().equalsIgnoreCase(value[1]);
        }

        return Arrays.stream(Country.values())
                     .filter(matcher)
                     .findAny();
    }