Serialize an Object to a File import java.util.Vector; import java.io.*; public class Queue extends Vector { /* ** FIFO, first in first out */ Queue() { super(); } void put(Object o) { addElement(o); } Object get() { if (isEmpty()) return null; Object o = firstElement(); removeElement(o); return o; } Object peek() { if (isEmpty()) return null; return firstElement(); } } //To serialize (save the Queue state to a file) : public static void main(String args[]) { Queue theQueue; theQueue = new Queue(); theQueue.put("element 1"); theQueue.put("element 2"); theQueue.put("element 3"); theQueue.put("element 4"); System.out.println(theQueue.toString()); // serialize the Queue System.out.println("serializing theQueue"); try { FileOutputStream fout = new FileOutputStream("thequeue.dat"); ObjectOutputStream oos = new ObjectOutputStream(fout); oos.writeObject(theQueue); oos.close(); } catch (Exception e) { e.printStackTrace(); } } //To unserialize (to load a previously saved Queue) : public static void main(String args[]) { Queue theQueue; theQueue = new Queue(); // unserialize the Queue System.out.println("unserializing theQueue"); try { FileInputStream fin = new FileInputStream("thequeue.dat"); ObjectInputStream ois = new ObjectInputStream(fin); theQueue = (Queue) ois.readObject(); ois.close(); } catch (Exception e) { e.printStackTrace(); } System.out.println(theQueue.toString()); }