手机客户端和Servlet通信求解失败原因,该如何解决

  //客户端通过此方法与Servlet通信             public void inTurnServer(){        try{            String url = "http://localhost:8080/my/Test";            str = tfd.getString();            HttpConnection conn = (HttpConnection)Connector.open(url);            // 设置请求类型为POST                conn.setRequestMethod(HttpConnection.POST);         // 设置一般的请求属性                conn.setRequestProperty("Content-Type",                        "application/x-www-form-urlencoded");                conn.setRequestProperty("User-Agent",                        "Profile/MIDP-1.0 Configuration/CLDC-1.0");                conn.setRequestProperty("Content-Language", "en-US");                conn.setRequestProperty("Accept", "application/octet-stream");                conn.setRequestProperty("Connection", "close");             String info = "str"+str;         // 转换显字节流                byte[] data = info.getBytes();         // 设置写入流的长度                conn.setRequestProperty("Content-Length", Integer                        .toString(data.length));            OutputStream os = conn.openOutputStream();                os.write(data);            os.close();                     // 得到Http响应代码                int rc = conn.getResponseCode();                // 正常响应                if (rc == HttpConnection.HTTP_OK)                {                    // 构建输入流                    DataInputStream dism = new DataInputStream(conn                            .openInputStream());                    // 读取服务器返回的字节流                    String result = dism.readUTF();                    dism.close();                    // 判断                    if (result.equals("true"))                    {                          System.out.println("OK!");                 }                    if (result.equals("false"))                    {                        System.out.println("ERROR!");               }                }                    }catch(Exception ex){            ex.printStackTrace();        }/////////////////////////////////////////////////////////////////////////////////////

    @Override//服务端Servlet    protected void doPost(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        String str = request.getParameter("str");        // 构建输出流            ByteArrayOutputStream baos = new ByteArrayOutputStream();            DataOutputStream dos = new DataOutputStream(baos);                  if("A".equals(str)){            dos.writeUTF("true");        }else{            dos.writeUTF("false");        }        byte[] data1 = baos.toByteArray();            // 设置服务器响应参数            response.setStatus(HttpServletResponse.SC_OK);            response.setContentLength(data1.length);            response.setContentType("application/octet-stream");            OutputStream os = response.getOutputStream();         os.write(data1);            os.close();    }