public void fillQueue() {
   try {
     BufferedReader reader = new BufferedReader(new FileReader(mSource));
     String line = null;
     int count = 0;
     while ((line = reader.readLine()) != null) {
       URL url = new URL(line);
       queue.enqueue(new BookThingISBNWorker(url));
       count++;
     }
   } catch (Exception e) {
     e.printStackTrace();
   }
 }
 public void start() {
   queue.start();
 }
 public boolean hasItems() {
   synchronized (queue) {
     return queue.remainingItems() > 0;
   }
 }