/**
     * Prints out frequencies of input characters (in percent)
     * @param source input file
     * @param encoding encoding of the file
     */
    public static void count(File source, String encoding) throws UnsupportedEncodingException, IOException{
        BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(source), encoding));
        
        TreeMap<Character, Integer> occurences = new TreeMap<Character, Integer>();

        String s = null;
        int counter = 0;
        while((s = reader.readLine())!= null){
            for(int i = 0; i < s.length(); i++){
                counter++;
                Character curr = (Character) s.charAt(i);
                if(occurences.get(curr) == null){
                    occurences.put(curr, new Integer(1));
                } else {
                    occurences.put(curr, occurences.get(curr).intValue() + 1);
                }
            }
        }

        for(Character ch : occurences.keySet()){
            System.out.println(ch.toString() + ": " + (occurences.get(ch).intValue()/(double)counter * 100));
        }
    }