java - Volley crashing app on service after long run

Question

Am implementing a service to get updates from server as below:

public class Myupdates extends Service {

    private static final String TAG = "AutoUpdates";
    private static final int started = 0;
    static SQLiteDatabase db;
    private boolean isRunning = false;

    private CountDownTimer timer;

    @Override
    public void onCreate() {
        this.db = openOrCreateDatabase("db", Context.MODE_PRIVATE, null);
        //Log.i(TAG, "Service onCreate");
        isRunning = true;
    }

    int mCount = 1;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        //Log.i(TAG, "Service onStartCommand");

        //Creating new thread for my service
        //Always write your long running tasks in a separate thread, to avoid ANR
        new Thread(new Runnable() {
            @Override
            public void run() {

                if (isRunning) {

                    new Timer().scheduleAtFixedRate(new TimerTask() {
                        @Override
                        public void run() {
                            updates();
                        }
                    }, 0, 30000);

                }
                //Stop service once it finishes its task
                //stopSelf();
            }
        }).start();

        return Service.START_STICKY;
    }

    @Override
    public IBinder onBind(Intent arg0) {
        //Log.i(TAG, "Service onBind");
        return null;
    }

    @Override
    public void onDestroy() {

        isRunning = false;

        //Log.i(TAG, "Service onDestroy");
    }

    /*
        HANDLE ADVERTS
    */
    protected void updates() {
        /*
            JSON
         */
        final JSONObject json = new JSONObject();
        final JSONObject manJson = new JSONObject();
        try {
            manJson.put("userid", "4444");
            manJson.put("version", "6.0");
            final String j = json.put("UPDATE", manJson).toString();
            final String base_url = "https://myweburl.com";
            // Instantiate the RequestQueue.
            RequestQueue queue = Volley.newRequestQueue(this);
            // Request a string response from the provided URL.
            StringRequest stringRequest = new StringRequest(Request.Method.POST, base_url, new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    //Log.i(TAG, "received "+response);
                    try {
                        JSONObject object = (JSONObject) new JSONTokener(response).nextValue();
                        String update = object.getString("UPDATE");
                    } catch (JSONException e) {
                        return;
                    }
                    return;
                }
            }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    //perform operation here after getting error
                    return;
                }
            }) {
                @Override
                protected Map<String, String> getParams() {
                    Map<String, String> params = new HashMap<String, String>();
                    //pack message into json
                    try {
                        params.put("data", j.toString());
                    } catch (Exception e) {
                        //Log.i(TAG,"Map error: Unable to compile post");
                    }
                    return params;
                }

                @Override
                public Map<String, String> getHeaders() throws AuthFailureError {
                    Map<String, String> params = new HashMap<String, String>();
                    params.put("Content-Type", "application/x-www-form-urlencoded");
                    return params;
                }
            };
            // Add the request to the RequestQueue.
            queue.add(stringRequest);
            // ends here
            return;
        } catch (Exception e) {
            //Log.i(TAG,"ERROR: Unable to get setup settings");
        } // end exception write
        return;
    }

}

However, after a long running of the service the app is crashing with the below error:

03-08 00:19:41.570 11239-11253/com.mobiledatabook.com.dialcode E/AndroidRuntime: FATAL EXCEPTION: Timer-0 Process: com.mobiledatabook.com.dialcode, PID: 11239 java.lang.OutOfMemoryError: pthread_create (stack size 16384 bytes) failed: Try again at java.lang.VMThread.create(Native Method) at java.lang.Thread.start(Thread.java:1029) at com.android.volley.RequestQueue.start(RequestQueue.java:152) at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:66) at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:78) at com.mobiledatabook.com.dialcode.Myupdates.iDialAutoUpdates(Myupdates.java:128) at com.mobiledatabook.com.dialcode.Myupdates$1$1.run(Myupdates.java:74) at java.util.Timer$TimerImpl.run(Timer.java:284)

Error: java.lang.OutOfMemoryError.

Could someone help me to improve this code so as to avoid crashing the app after long running of the service?

Answer 1

This is occurring because you are creating the RequestQueue instance multiple times by passing the activity context. You should create the instance once using an Application class and then use it again and again whenever needed. Create an application class like this,

public class AppController extends Application {
    private static AppController sInstance;
    private RequestQueue mRequestQueue;

    @Override
    public void onCreate() {
    super.onCreate();

    sInstance = this;
    }

    public static synchronized AppController getInstance() {
    return sInstance;
    }

    public RequestQueue getRequestQueue() {

            if (mRequestQueue == null) {
                mRequestQueue = Volley.newRequestQueue(getApplicationContext());
            }

            return mRequestQueue;
        }

}

Then use it like this

RequestQueue queue=AppController.getInstance().getRequestQueue();

NOTE : By passing the context to request queue again and again , you are filling up your ram, which leads to an OutOfMemoryException when no more space can be allocated

As mentioned in android's official docs here ,

A key concept is that the RequestQueue must be instantiated with the Application context, not an Activity context. This ensures that the RequestQueue will last for the lifetime of your app, instead of being recreated every time the activity is recreated (for example, when the user rotates the device).