public static int[] features(final String features) {
        if (features.length() == 0) return null;
        List<Integer> buffer   = new ArrayList<Integer>(); 
        String[]      elements = features.split(FEATURE_SEPERATOR);
        for (String e : elements) {
            String f = e.trim();
            if (f.length() > 0) {
                buffer.add(Integer.parseInt(f));
            }
        }
        int[] result = new int[buffer.size()];
        for (int i = 0; i < result.length; i++) {
            result[i] = buffer.get(i);
        }
        return result;
    }