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POJSON Array NullPointerException
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copied!<p>What would be the best way to parse this in an Android app? I am getting java.lang.NullPointerException when I run the app. Please take a look at my code and let me know if you have any suggestions.</p> <pre><code>{"begin":[{"id":1,"name":"Bob","size":2}],"open":[{"id":1,"name":"Mike","size":2}]} </code></pre> <p>This is the code that I have.</p> <pre><code>public class MainFragment extends Fragment { public MainFragment() {} //URL to get JSON Array private String url = "URL..."; //JSON Node Names private static final String TAG_BEGIN = "begin"; private static final String TAG_ID = "id"; private static final String TAG_NAME = "name"; private static final String TAG_SIZE = "size"; JSONArray begin = null; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_main, container, false); new JSONParse().execute(); return rootView; } private class JSONParse extends AsyncTask<String, String, JSONObject> { private ProgressDialog pDialog; @Override protected void onPreExecute() { super.onPreExecute(); pDialog = new ProgressDialog(HomeActivity.this); pDialog.setMessage("Getting Data ..."); pDialog.setIndeterminate(false); pDialog.setCancelable(true); pDialog.show(); } @Override protected JSONObject doInBackground(String... args) { JSONParser jParser = new JSONParser(); // Getting JSON from URL JSONObject json = jParser.getJSONFromUrl(url); return json; } @Override protected void onPostExecute(JSONObject json) { pDialog.dismiss(); try { // Getting JSON Array begin = json.getJSONArray(TAG_BEGIN); JSONObject c = begin.getJSONObject(0); // Storing JSON item in a Variable String id = c.getString(TAG_ID); String name = c.getString(TAG_NAME); String size = c.getString(TAG_SIZE); } catch (JSONException e) { e.printStackTrace(); } } } } </code></pre> <p>When I run the activity I get this error:</p> <pre><code>FATAL EXCEPTION: main java.lang.NullPointerException at ...$MainFragment$JSONParse.onPostExecute(MainActivity.java:399) at ...$MainFragment$JSONParse.onPostExecute(MainActivity.java:373) </code></pre> <p>Which is...</p> <pre><code>begin = json.getJSONArray(TAG_BEGIN); </code></pre> <p>and...</p> <pre><code>private class JSONParse extends AsyncTask<String, String, JSONObject> { </code></pre>

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