chains().of(stream -> stream.forEach(c -> c.update(user)));
    }

    public boolean changePassword(final String username, final String password) {
        return chains().get(stream -> stream.allMatch(c -> c.changePassword(username, password)));
    }

    public void delete(final User user) {
        chains().of(stream -> stream.forEach(c -> c.delete(user)));
    }

    public User load(final User user) {

    }

    protected boolean isEmptyArray(final String[] values) {
        if (values == null || values.length == 0) {
            return true;
        }
        return stream(values).get(stream -> stream.allMatch(StringUtil::isBlank));
    }

    protected static String[] simplifyArray(final String[] values) {
        return stream(values).get(stream -> stream.filter(StringUtil::isNotBlank).distinct().toArray(n -> new String[n]));