Can an Android App connect directly to an online mysql database

Android 3.3 API 18

Hello,

I am developing my first App using android. The App will have to connect to an online database to store user data.

I am looking for a cloud storage with a MySQL database included. However, can my App connect directly to this MySQL database and push and pull data from it? Or is there other things I need to do?

Many thanks for any suggestions,

Solution 1:

Yes you can do that.

Materials you need:

WebServer
A Database Stored in the webserver
And a little bit android knowledge :)
Webservices (json ,Xml...etc) whatever you are comfortable with

1. First set the internet permissions in your manifest file

 <uses-permission android:name="android.permission.INTERNET" />

2. Make a class to make an HTTPRequest from the server (i am using json parisng to get the values)

for eg:

    public class JSONfunctions {

    public static JSONObject getJSONfromURL(String url) {
        InputStream is = null;
        String result = "";
        JSONObject jArray = null;

        // Download JSON data from URL
        try {
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost(url);
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            is = entity.getContent();

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

        // 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");
            }
            is.close();
            result = sb.toString();
        } catch (Exception e) {
            Log.e("log_tag", "Error converting result " + e.toString());
        }

        try {

            jArray = new JSONObject(result);
        } catch (JSONException e) {
            Log.e("log_tag", "Error parsing data " + e.toString());
        }

        return jArray;
    }
}

3. In your MainActivity Make an object of the class JsonFunctions and pass the url as an argument from where you want to get the data

eg:

JSONObject jsonobject;

jsonobject = JSONfunctions.getJSONfromURL("http://YOUR_DATABASE_URL");

4. And then finally read the jsontags and store the values in an arraylist and later show it in listview if you want

and if you have any problem you can follow this blog he gives excellent android tutorials AndroidHive

Since the above answer i wrote was long back and now HttpClient, HttpPost,HttpEntity have been removed in Api 23. You can use the below code in the build.gradle(app-level) to still continue using org.apache.httpin your project.

android {
    useLibrary 'org.apache.http.legacy'
    signingConfigs {}
    buildTypes {}
}

or You can use HttpURLConnection like below to get your response from server

public String getJSON(String url, int timeout) {
HttpURLConnection c = null;
try {
    URL u = new URL(url);
    c = (HttpURLConnection) u.openConnection();
    c.setRequestMethod("GET");
    c.setRequestProperty("Content-length", "0");
    c.setUseCaches(false);
    c.setAllowUserInteraction(false);
    c.setConnectTimeout(timeout);
    c.setReadTimeout(timeout);
    c.connect();
    int status = c.getResponseCode();

    switch (status) {
        case 200:
        case 201:
            BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
            StringBuilder sb = new StringBuilder();
            String line;
            while ((line = br.readLine()) != null) {
                sb.append(line+"\n");
            }
            br.close();
            return sb.toString();
    }

} catch (MalformedURLException ex) {
    Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
    Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
} finally {
   if (c != null) {
      try {
          c.disconnect();
      } catch (Exception ex) {
         Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
      }
   }
}
return null;

}

or You can use 3rd party Library like Volley, Retrofit to call the webservice api and get the response and later parse it with using FasterXML-jackson, google-gson.

Solution 2:

What you want to do is a bad idea. It would require you to embed your username and password in the app. This is a very bad idea as it might be possible to reverse engineer your APK and get the username and password to this publicly facing mysql server which may contain sensitive user data.

I would suggest making a web service to act as a proxy to the mysql server. I assume users need to be logged in, so you could use their username/password to authenticate to the web service.

Solution 3:

You can use PHP, JSP, ASP or any other server side script to connect with mysql database and and return JSON data that you can parse it to in your android app this link how to do it