PoPClient client = new PoPClient("pop.orange.fr", 995, "login@wanadoo.fr", "password", 30000, true);
client.setMaxRetrievedMessages(4);
client.getChangeEvent().addObserver(new Observer()
{

    @Override
    public void update(Observable o, Object arg)
    {
        // State changed
        if(arg.equals(IDLE))
        {
            client.quit();
        }
    }
});
client.connect();