public void storePolicyToObjectFile(String filename) {
        ObjectOutputStream output = null;
        try {
            output = new ObjectOutputStream(new FileOutputStream(filename));
            output.writeObject(policy);
            output.close();
        } catch (IOException ex) {
            Logger.getLogger(PolicyController.class.getName())
                  .log(Level.SEVERE, null, ex);
        } finally {
            try {
                output.close();
            } catch (IOException ex) {
                Logger.getLogger(PolicyController.class.getName())
                      .log(Level.SEVERE, null, ex);
            }
        }