Question

public class PrimeServerSideServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    @Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp)
        throws IOException {
        processRequest(req, resp);

        String user = req.getParameter("id0");

        int primeNumberCounter = 1;
        long upperLimit = 10000000;
        //resp.setContentType("text/plain");
        PrintWriter writer = resp.getWriter();

        while (++i <= upperLimit) {

            long i1 = (long) Math.ceil(Math.sqrt(i));
            boolean isPrimeNumber = false;
            while (i1 > 1) {
                if ((i != i1) && (i % i1 == 0)) {
                    isPrimeNumber = false;
                    break;
                } else if (!isPrimeNumber) {
                    isPrimeNumber = true;
                }

                --i1;
            }

            if (isPrimeNumber) {
                writer.write(String.valueOf(i));
                writer.write("\n");
                ++primeNumberCounter;
            }

            writer.flush();
        }
        writer = resp.getWriter();
        writer.write("value" + user);
    } 
    private void processRequest(HttpServletRequest req, HttpServletResponse resp)throws IOException {
        // TODO Auto-generated method stub
    }
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doPost(req, resp);
    }
}

Android端密码

private String s;
EditText numDisplay;
Button calculateNow;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    numDisplay= (EditText)findViewById(R.id.editText1);
    calculateNow = (Button)findViewById(R.id.button1);
    //s=numDisplay.toString();  
    calculateNow.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            {

                new MyAsyncTask().execute(numDisplay.getText().toString());     

            } }
     } );
}
private class MyAsyncTask extends AsyncTask<String, Integer, Double>{
        protected Double doInBackground(String... params) {

            postData(params[0]);
            return null;
        }
        protected void onPostExecute(Double result){
            //pb.setVisibility(View.GONE);
            Toast.makeText(getApplicationContext(), "command sent", Toast.LENGTH_LONG).show();
        }

        protected void onProgressUpdate(Integer... progress){
            //pb.setProgress(progress[0]);
        }
        public void postData(String valueIWantToSend) {
            // Create a new HttpClient and Post Header
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost("http://localhost:8888");

            try {
                // Add your data
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("id0", valueIWantToSend));
                httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                // Execute HTTP Post Request
                HttpResponse response = httpclient.execute(httppost);

            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
            } catch (IOException e) {
                // TODO Auto-generated catch block
            }
        }}}

使用post和servlet端从android端发送一个整数值，计算用户输入的值的素数。

但是我在servlet中打印用户的值时得到null值。我在android和服务器端都使用了post方法我得到错误“http get不支持这个url”，我更改了servlet端代码获取值通过get方法和get中的post方法调用。

我通过帖子发送我的数据，请求类型得到了尽管我正在使用post.I谷歌很多这个上下文但没有得到任何解决方案。我没有得到响应只发送请求。任何帮助赞赏。

在servlet中接收null

0 个答案: