private void createNoteFromGSAKUserdata() {
        if (StringUtils.isBlank(cache.getPersonalNote())) {
            final StringBuilder buffer = new StringBuilder();
            for (final String anUserData : userData) {
                if (StringUtils.isNotBlank(anUserData)) {
                    buffer.append(' ').append(anUserData);
                }
            }
            final String note = buffer.toString().trim();
            if (StringUtils.isNotBlank(note)) {
                cache.setPersonalNote(note, true);
            }
        }
    }
create a cache note from the UserData1 to UserData4 fields supported by GSAK
main/src/main/java/cgeo/geocaching/files/GPXParser.java