public static void main(String[] args) throws FileNotFoundException, 
    UnsupportedEncodingException, IOException, ClassNotFoundException {
        final File folder = new File("D:\\_docs2");
         
        Holder h = new Holder();
        h.buildIndexes(folder);
        
        h.search("Thinking in Java");
        h.showSimilarity();
        h.showLeaders();
        h.showFollowers();
    }