Question

I want to connect mysql database locally with android emulator. I used http GET and POST methods for accessing data from Google Cloud SQL with app engine but i want to connect it with locally using phpmyadmin..

when i use following code it show Toast for connection failed

        String result = "";
        //the year data to send
        ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
        nameValuePairs.add(new BasicNameValuePair("name","Hammad"));

        //http post
        try{
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost("http://localhost/myApp/read_data.php");
                httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpResponse response = httpclient.execute(httppost); 
                HttpEntity entity = response.getEntity();
                is = entity.getContent();

                Log.e("log_tag", "connection success ");
                Toast.makeText(getApplicationContext(), "pass", Toast.LENGTH_SHORT).show();
        }catch(Exception e){
                Log.e("log_tag", "Error in http connection "+e.toString());
                Toast.makeText(getApplicationContext(), "Connection fail", Toast.LENGTH_SHORT).show();

        }
        //convert response to string
        try{
                BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
                StringBuilder sb = new StringBuilder();
                String line = null;
                while ((line = reader.readLine()) != null) {
                        sb.append(line + "\n");
                        Toast.makeText(getApplicationContext(), "Input Reading pass", Toast.LENGTH_SHORT).show();
                }
                is.close();

                result=sb.toString();
        }catch(Exception e){
               Log.e("log_tag", "Error converting result "+e.toString());
            Toast.makeText(getApplicationContext(), " Input reading fail", Toast.LENGTH_SHORT).show();

        }

        //parse json data
        try{
                JSONArray jArray = new JSONArray(result);
                for(int i=0;i<jArray.length();i++){
                       JSONObject json_data = jArray.getJSONObject(i);
                        Log.i("log_tag","id: "+json_data.getInt("user_id")+
                                ", Username: "+json_data.getString("username")+
                                ", Name: "+json_data.getInt("name")+
                                ", City: "+json_data.getInt("city")
                        );
                        Toast.makeText(getApplicationContext(), "JsonArray pass", Toast.LENGTH_SHORT).show();
               }

        }catch(JSONException e){
                Log.e("log_tag", "Error parsing data "+e.toString());
                Toast.makeText(getApplicationContext(), "JsonArray fail", Toast.LENGTH_SHORT).show();
        }
    }

  }

Answer 1

If you’re running this within the emulator localhost:3306 won’t work. Replace that with the IP address of the machine running MySQL. So for example if your local dev machine (running MySQL) uses IP 192.168.0.10, change that to 192.168.0.10:3306.

Just to expand a bit – when you attempt to access http://localhost:3306 within the emulator (or even on a device) it tries to connect to the port 3306 on the loopback address (on the emulator/device). You obviously don’t have the SQL service running on the android so this doesn’t make sense.

Also, depending on your OS configuration, you may have to open port 3306 in your firewall.

Edit: Warren’s tip (below) leads me to the details in the Android docs. May want to stick with 10.0.2.2 if you don’t want to mess around with your OS’ firewall.