Android客户端与服务器HTTP交互，数据以json格式传输

    /**        * HTTP请求服务器        * @author lz        */        public class HttpRequestServer{            private String serverCategoryStr = "http://192.168.1.2:8080/ChatXXX/";// 服务器地址            private String url = "http://192.168.1.4:8080/ChatXXX/login";            private static final int REQUEST_TIMEOUT = 1 * 1000;// 设置请求超时10秒钟            private static final int SO_TIMEOUT = 5 * 1000; // 设置等待数据超时时间10秒钟            private static final int type=-1;//请求Type                    public HttpRequestServer() {                    }                /**        * 用户登录        * @param name        * @param pwd        * @return        * @throws ClientProtocolException        * @throws JSONException        * @throws IOException        */            public JSONObject login(String name, String pwd)                    throws ClientProtocolException, JSONException, IOException {                url = serverCategoryStr + Constants.URL_LOGIN;                JSONObject param = new JSONObject();                param.put(Constants.TYPE, Constants.LOGIN);                param.put(Constants.USER_NAME, name);                param.put(Constants.USER_PASSWORD, pwd);                return requestServer(Constants.LOGIN, param);            }                        /**        * 通用请求服务器函数        * @param userId        * @param name        * @param pwd        * @param requestType        * @param status        * @return        * @throws JSONException        * @throws ClientProtocolException        * @throws IOException        */        private JSONObject requestServer(String requestType,JSONObject param) throws JSONException,                    ClientProtocolException, IOException {                // 不加这一段则会报错，错误信息为android.os.networkonmainthreadexception                // 在Android2.2以后必须添加以下代码                // 本应用采用的Android4.0                // 设置线程的策略                StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()                        .permitAll() // 此处为允许磁盘读写和网络访问                        .penaltyLog() // 打印logcat，当然也可以定位到dropbox，通过文件保存相应的log                        .build());                HttpPost request = new HttpPost(url);                // 绑定到请求 Entry                StringEntity se = new StringEntity(param.toString(),"utf-8");                request.setEntity(se);                // 发送请求                HttpClient httpclient = getHttpClient();                HttpResponse httpResponse = httpclient.execute(request);                JSONObject result = null;                int code=httpResponse.getStatusLine().getStatusCode();                    if (code == 200) {                    // 得到应答的字符串，这也是一个 JSON 格式保存的数据                    String retSrc = null;                    retSrc = EntityUtils.toString(httpResponse.getEntity(),"utf-8");                    JSONObject jtmpJsonObject = new JSONObject(retSrc);                    String str = jtmpJsonObject.getString("dataMap");// 此处"dataMap"与服务器关联                    result = new JSONObject(str);                }                return result;            }            private HttpClient getHttpClient() {                BasicHttpParams httpParams = new BasicHttpParams();                HttpConnectionParams.setConnectionTimeout(httpParams, REQUEST_TIMEOUT);                HttpConnectionParams.setSoTimeout(httpParams, SO_TIMEOUT);                HttpClient httpclient = new DefaultHttpClient(httpParams);                return httpclient;            }