private void readImages(String folderpath) {
   String test = "";
   int offset = 0;
   // get words from db
   String sql = "SELECT word, id FROM word LIMIT " + NUM_CLASSES + " OFFSET " + offset;
   wordClasses = new String[NUM_CLASSES];
   int classes[] = new int[NUM_CLASSES];
   int index = 0;
   try {
     ResultSet rs = db.select(sql);
     while (rs.next()) {
       wordClasses[index] = rs.getString("word");
       classes[index] = rs.getInt("id");
       index++;
     }
   } catch (ClassNotFoundException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
   } catch (SQLException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
   }
   int number = 0;
   String data2 = "";
   for (int j = 0; j < wordClasses.length; j++) {
     System.out.println(j);
     int files = new File(folderpath + "\\" + wordClasses[j]).listFiles().length;
     for (int k = 1; k <= files; k++) {
       File file = new File(folderpath + "\\" + wordClasses[j] + "\\" + "word (" + k + ").jpg");
       Shorthand word = new Shorthand(file, wordClasses[j], classes[j]);
       testingSamples.add(word);
     }
   }
 }