java.lang.NullPointerException in json error

Question

At First run everthing is good it's running with no error but when i try to refresh it using swiperefreshlayout boom! it crash :( i got this error.

 java.lang.NullPointerException
        at parse.FeedDataParser.getFeed(FeedDataParser.java:25)
        at better.business.solution.feedssample.SampleGraph$1.onCompleted(SampleGraph.java:57)
        at com.facebook.GraphRequest$5.run(GraphRequest.java:1243)
        at android.os.Handler.handleCallback(Handler.java:615)
        at android.os.Handler.dispatchMessage(Handler.java:92)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:4745)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
        at dalvik.system.NativeStart.main(Native Method)

this is my code in FeedDataParser

    public List<ResultFeed> getFeed(){

    try {
        List<ResultFeed> result = new ArrayList<ResultFeed>();
        JSONObject jsonObject = mFeedJson.getJSONObject("feed");
        JSONArray jsonArray = jsonObject.getJSONArray("data");
        for(int ctr=0; ctr<jsonArray.length();ctr++){
             ResultFeed resultFeed = new ResultFeed(jsonArray.getJSONObject(ctr));
             result.add(resultFeed);
        }
        return result;


    } catch (JSONException e) {
        e.printStackTrace();
    }
    return null;
}

and my asynctask which call everytime i refresh my app.

    private List<ResultFeed> feedItemList;
    private MyAdapter myAdapter;
    private SwipeRefreshLayout mSwipeRefreshLayout;
   public InitializeApplicationsTask(Context context,AccessToken accessToken,OnDataFullFeedListener dataFullFeedListener,List<ResultFeed> feedItemList,MyAdapter myAdapter,RecyclerView mRecyclerView,SwipeRefreshLayout mSwipeRefreshLayout) {

        this.feedItemList = feedItemList;
        this.myAdapter = myAdapter;
        this.mSwipeRefreshLayout = mSwipeRefreshLayout;

        GraphRequestFeeds graphRequestFeeds = new GraphRequestFeeds(dataFullFeedListener,context);
        graphRequestFeeds.resultInBatchReq(accessToken);

        Log.e("constructor",""+accessToken);

    }

    @Override
    protected void onPreExecute() {

        super.onPreExecute();
        Log.e("onPre", "jac");
    }

    @Override
    protected List<ResultFeed> doInBackground(Void... params) {


        Log.e("doinBack", "jac");
        Log.e("feeditemlist1",""+feedItemList);
        return null;
    }

    @Override
    protected void onPostExecute(List<ResultFeed> resultFeeds) {
        super.onPostExecute(resultFeeds);
           mSwipeRefreshLayout.setRefreshing(false);

    }

Plsss help me :((((

As the stack trace says, the exception happens in `FeedDataParser.java` at line 25. Something is `null` there. You're probably calling a method on a variable that is `null`. — Jesper, Jun 11 '15 at 07:14
{ "feed": { "data": [ { the actual json is something like this. — Marlon Aromin, Jun 11 '15 at 07:14
JSONObject jsonObject = mFeedJson.getJSONObject("feed"); this is the line 25 but why is it null? im trying to check if it's null but still the same. do you see my asynctask in refresh? is it correct? — Marlon Aromin, Jun 11 '15 at 07:15
If the line 25 is the one commented by you, it means `mFeedJson` itself is null. — Codebender, Jun 11 '15 at 07:17
but it has a value , it's happening only when i call the it on InitializeApplicationsTask. — Marlon Aromin, Jun 11 '15 at 07:19

java.lang.NullPointerException in json error

0 Answers0