}

    public void setPostalCode(String value) {
        registerModifiedProperty("postalCode");
        this.postalCode = value;
    }

    public String getPreferredLanguage() {
        checkSpecifiedProperty("preferredLanguage");
        return convertEmptyToNull(preferredLanguage);
    }

    public void setPreferredLanguage(String value) {

                "postalAddress");
        setupEpg(_epgMap, et -> ((User) et).getPostalCode(), (et, vl) -> ((User) et).setPostalCode(DfTypeUtil.toString(vl)), "postalCode");
        setupEpg(_epgMap, et -> ((User) et).getPreferredLanguage(), (et, vl) -> ((User) et).setPreferredLanguage(DfTypeUtil.toString(vl)),
                "preferredLanguage");

    }

    @Test
    public void test_user_preferredLanguage() {
        final User user = new User();
        assertNull(user.getPreferredLanguage());

        user.setPreferredLanguage("en");
        assertEquals("en", user.getPreferredLanguage());
    }

    @Test
    public void test_user_destinationIndicator() {
        final User user = new User();

                        .forEach(v -> modifyDeleteEntry(modifyList, attrDisplayName, v)));
        final String attrPreferredLanguage = fessConfig.getLdapAttrPreferredLanguage();
        OptionalUtil.ofNullable(user.getPreferredLanguage())
                .filter(StringUtil::isNotBlank)
                .ifPresent(s -> modifyReplaceEntry(modifyList, attrPreferredLanguage, s))