private String httpRequest(Map<String, String> param, String method) {
        Log.d("httpRequest", "start to send http request");
        // 添加其他默认需要的参数
        param.put("method", method);
        if (!param.containsKey("v")){
            param.put("v", Ver);
        }
        if (!param.containsKey("appKey")){
            param.put("appKey", AppKey);
        }
        if (!param.containsKey("uzone_token") && UzoneToken != null){
            param.put("uzone_token", UzoneToken);
        }
        // 生成请求用户的参数
        Map<String, String> nameValuePairs = this.buildRequestParam(param);
        String url            = this.buildRequestUri(nameValuePairs, RestServer);
        String response       = "";
        HttpClient client     = new HttpClient();
        InputStream in        = null;
        BufferedReader reader = null;
        try{
            HttpMethod getMethod = new GetMethod(url);
            client.executeMethod(getMethod);
            in     = getMethod.getResponseBodyAsStream();
            reader           = new BufferedReader(new InputStreamReader(in));
            StringBuilder sb = new StringBuilder();
            String temp      = ""; 
            while((temp = reader.readLine()) != null){
                sb.append(temp);
            }   
            response = sb.toString();
            // 关闭链接
            getMethod.releaseConnection(); 
        }catch (Exception e) {
            // TODO: handle exception
        }finally{
            try{
                if(in != null){
                    in.close();
                }   
                if(reader != null){
                    reader.close();
                }
            }catch (IOException e) {
                // TODO: handle exception
            }
        }
        Log.d("httpRequest", "Server Resonse: " + response);
        return response;
    }