Core/src/main/java/org/openestate/io/core/LocaleUtils.java
public static String getCountryISO3FromISO2(String iso2Code) {
        iso2Code = StringUtils.trimToNull(iso2Code);
        if (iso2Code == null) return null;
        if (iso2Code.length() == 2) {
            Locale countryLocale = new Locale(iso2Code, iso2Code);
            String iso3Code = StringUtils.trimToNull(countryLocale.getISO3Country());
            if (iso3Code != null) return iso3Code;
        }
        return null;
    }
public static String getCountryISO3FromISO2(String iso2Code) {
        iso2Code = StringUtils.trimToNull(iso2Code);
        if (iso2Code == null) return null;
        if (iso2Code.length() == 2) {
            Locale countryLocale = new Locale(iso2Code, iso2Code);
            String iso3Code = StringUtils.trimToNull(countryLocale.getISO3Country());
            if (iso3Code != null) return iso3Code;
        }
        return null;
    }
Create an ISO-3 country code from an ISO-2 country code.

@param iso2Code ISO-2 country code
@return ISO-3 country code or null, if no code was found