// From http://code.calum.org/
		public static byte[] objectToByteArray(Object o){
        ByteArrayOutputStream baos  = new ByteArrayOutputStream();
        ObjectOutputStream  oos;
        try {
            oos = new ObjectOutputStream(baos);
            oos.writeObject(o);
            oos.flush();
            byte[] ret = baos.toByteArray();
    //        System.out.println("objectToByteArray: result is " + ret.length + " bytes");
            return ret;
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        return null;
    }