private static void addRef (String ref,
private void addRef (String ref,
    private static void addRef (String ref,                                List<String> list)    {        // The ref may be a plain file name or the name of a pack        // that lists ref(s). This is signalled by a starting '@'        // character in ref        if (ref.startsWith("@")) {            // File with other refs inside            String pack = ref.substring(1);            try {                BufferedReader br = new BufferedReader                    (new FileReader(pack));                String newRef;                try {                    while ((newRef = br.readLine()) != null) {                        addRef(newRef.trim(), list);                    }                    br.close();                } catch (IOException ex) {                    logger.warning("IO error while reading file '" + pack                                   + "'");                }            } catch (FileNotFoundException ex) {                logger.warning("Cannot find file '" + pack + "'");            }        } else        // Plain file name            if (ref.length() > 0) {                list.add(ref);            }    }