public List<String> getAllAddresses() {
            ArrayList<String> addresses = new ArrayList<String>();
            for (Map.Entry<String, String> entry : to.entrySet())
                addresses.add(entry.getKey());
            for (Map.Entry<String, String> entry : cc.entrySet())
                addresses.add(entry.getKey());
            for (Map.Entry<String, String> entry : bcc.entrySet())
                addresses.add(entry.getKey());
            return addresses;
        }