Question

我想在Android应用程序中向移动设备发送一个localhost服务器，json数据。我使用真正的手机作为客户端来测试我的应用程序。我正在使用API Rest发送数据，而Servlet则用于接收数据。

我有连接错误。我的手机没有连接到服务器，我不知道为什么......

这是客户端代码：

 public void send(){
    StringBuilder sb = new StringBuilder();  
    String http = "http://10.0.2.2/W7TurismoServer/Servlet";  
    ArrayList<String> mostraArray=show();
    HttpURLConnection urlConnection=null;  
    try {  
        URL url = new URL(http);  
        urlConnection = (HttpURLConnection) url.openConnection();
        urlConnection.setDoOutput(true);   
        urlConnection.setRequestMethod("POST");  
        urlConnection.setUseCaches(false);  
        urlConnection.setConnectTimeout(10000);  
        urlConnection.setReadTimeout(10000);  
        urlConnection.setRequestProperty("Content-Type","application/json");   
        urlConnection.setRequestProperty("Host","http://10.0.2.2/W7TurismoServer/Servlet");

        urlConnection.connect();  

        //Create JSONObject here*/
        JSONObject jsonParam = new JSONObject();
        JSONArray arraypref=new JSONArray();

        arraypref.put(mostraArray);
        jsonParam.put("stringList",arraypref);
        System.out.println(jsonParam);
        OutputStreamWriter out = new   OutputStreamWriter(urlConnection.getOutputStream());
        out.write(jsonParam.toString());
        out.close();  

        int HttpResult =urlConnection.getResponseCode();  
        if(HttpResult ==HttpURLConnection.HTTP_OK){  
            BufferedReader br = new BufferedReader(new InputStreamReader(  
                urlConnection.getInputStream(),"utf-8"));  
            String line = null;  
            while ((line = br.readLine()) != null) {  
                sb.append(line + "\n");  
            }  
            br.close();  

            System.out.println(""+sb.toString());  

        }else{  
                System.out.println(urlConnection.getResponseMessage());  
        }  
    } catch (MalformedURLException e) {  

             e.printStackTrace();  
    }  
    catch (IOException e) {  

        e.printStackTrace();  
        } catch (JSONException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }finally{  
        if(urlConnection!=null)  
        urlConnection.disconnect();  
    }  
}

show（）方法返回ArrayList，我将把这个数组发送到服务器。

这是服务器代码：

 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
public void doPost(HttpServletRequest request, HttpServletResponse response)
          throws ServletException, IOException {

    PrintWriter out= response.getWriter();
    out.println("sono11");

    System.out.println("stouk do");
          StringBuffer jb = new StringBuffer();
          String line = null;
          try {
            BufferedReader reader = request.getReader();
            while ((line = reader.readLine()) != null)
              jb.append(line);
          } catch (Exception e) { /*report an error*/ }

          try {

            JSONObject jsonObject = JSONObject.fromObject(jb.toString());
            System.out.println("sono venuto,"+jsonObject);
          } catch (ParseException e) {
            // crash and burn
            throw new IOException("Error parsing JSON request string");
          }

}

这个课程在W7TurismoServer。提前感谢您的帮助。

Answer 1

很可能是NetworkOnMainThreadException，它告诉您在UI线程上进行HTTP连接，并且因为它可能导致无响应，所以不鼓励。

Quick Fix已在其他StackOverflow线程中得到解答，但为了获得更好的解决方案，您需要使用AsyncTask。

将数据从android发送到服务器localhost

1 个答案: