Android Emulator强制关闭localhost

Question

我的应用程序正在关闭错误，当我尝试连接MySQL服务器（通过xampp）时，请帮助我。

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        String result =null;
        InputStream is=null;
        StringBuilder sb =null;

        try{
            HttpClient httpclient=new DefaultHttpClient();
            HttpPost httppost=new HttpPost("http:/localhost/db.php");
            List<? extends NameValuePair> nameValuePairs = null;
            httppost.setEntity((HttpEntity) new UrlEncodedFormEntity(nameValuePairs));
            HttpResponse response =httpclient.execute(httppost);
            HttpEntity entity =response.getEntity();
            is=entity.getContent();

        }
        catch(Exception e){
            Log.e("log_tag", "Error in httpconnection"+e.toString());
        }

        try{
            BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
             sb = new StringBuilder();
             sb.append(reader.readLine()+ "\n");
             String line ="0";
             while ((line=reader.readLine())!=null) {
                 sb.append(line +"\n");
             }
             is.close();
             result=sb.toString();
        }catch(Exception e){
            Log.e("log_tag", "Error converting result"+ e.toString());
        }
            @SuppressWarnings("unused")
            String refno,name;
            try{
                JSONArray jArray = new JSONArray(result);
                JSONObject json_data=null;

                for(int i=0;i<jArray.length();i++){
                    json_data = jArray.getJSONObject(1);
                    refno =json_data.getString("refno");
                    name = json_data.getString("name");
                }
            }catch(JSONException e1){
                Toast.makeText(getBaseContext(), "No data",Toast.LENGTH_LONG).show();
            }catch(ParseException e1){
                e1.printStackTrace();

                }

        }

}