一个线程中的两个message如何避免

 //获取好友分组的线程       new Thread(new Runnable() {            @Override            public void run() {                // TODO Auto-generated method stub                Map<String, Object> params = new HashMap<String, Object>();                map = new HashMap<String, Object>();                friendGroup = new ArrayList<FriendGroup>();                                     friendList = new ArrayList<FriendGroup>();                params.put("ID", LoginActivity.userID);                //获取用户组的输入流                InputStream group_is = WebServer.hcPostData("GetFriendGroup",                        "FriendApp.ashx", params);                                     InputStream friends_is = WebServer.hcPostData("GetFriendList",                        "FriendApp.ashx", params);                parser = new XMLParser();                try {                    friendGroup = parser.FriendGroupParser(group_is);                                              friendList = parser.FriendGroupParser(group_is);                    Message message = new Message();                    message.obj = friendGroup;                    mHandler.sendMessage(message);                } catch (Exception e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }        }).start();               private Handler mHandler = new Handler() {        @SuppressWarnings("unchecked")        @Override        public void handleMessage(Message msg) {                        // TODO Auto-generated method stub            friendGroup = (ArrayList<FriendGroup>) msg.obj;             GetAllFriend();            super.handleMessage(msg);        }    };

static final int SEND_GROUP = 1;static final int SEND_LIST = 2;