FATAL EXCEPTION: AsyncTask, receiving json

Im doing some database work in my app, i want to pull all the locations from my web database and show it in my listview in the app. Ive created the “API” where the respons is Json.

The link where the json is: http://000100023.host56.com/db_all.php

Using this tutorial: http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/

The Logcat:

11-14 16:50:21.508: E/AndroidRuntime(22809): FATAL EXCEPTION: AsyncTask #1
11-14 16:50:21.508: E/AndroidRuntime(22809): Process: com.spxc.nightclubratings, PID: 22809
11-14 16:50:21.508: E/AndroidRuntime(22809): java.lang.RuntimeException: An error occured while executing doInBackground()
11-14 16:50:21.508: E/AndroidRuntime(22809):    at android.os.AsyncTask$3.done(AsyncTask.java:300)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.FutureTask.run(FutureTask.java:242)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.lang.Thread.run(Thread.java:841)
11-14 16:50:21.508: E/AndroidRuntime(22809): Caused by: java.lang.NullPointerException
11-14 16:50:21.508: E/AndroidRuntime(22809):    at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.doInBackground(SearchLocationActivity.java:132)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.doInBackground(SearchLocationActivity.java:1)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at android.os.AsyncTask$2.call(AsyncTask.java:288)
11-14 16:50:21.508: E/AndroidRuntime(22809):    at java.util.concurrent.FutureTask.run(FutureTask.java:237)
11-14 16:50:21.508: E/AndroidRuntime(22809):    ... 4 more
11-14 16:50:22.199: E/WindowManager(22809): android.view.WindowLeaked: Activity com.spxc.nightclubratings.SearchLocationActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{42313208 V.E..... R......D 0,0-729,192} that was originally added here
11-14 16:50:22.199: E/WindowManager(22809):     at android.view.ViewRootImpl.<init>(ViewRootImpl.java:346)
11-14 16:50:22.199: E/WindowManager(22809):     at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
11-14 16:50:22.199: E/WindowManager(22809):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.Dialog.show(Dialog.java:286)
11-14 16:50:22.199: E/WindowManager(22809):     at com.spxc.nightclubratings.SearchLocationActivity$LoadAllProducts.onPreExecute(SearchLocationActivity.java:119)
11-14 16:50:22.199: E/WindowManager(22809):     at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
11-14 16:50:22.199: E/WindowManager(22809):     at android.os.AsyncTask.execute(AsyncTask.java:535)
11-14 16:50:22.199: E/WindowManager(22809):     at com.spxc.nightclubratings.SearchLocationActivity.onCreate(SearchLocationActivity.java:59)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.Activity.performCreate(Activity.java:5243)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.ActivityThread.access$700(ActivityThread.java:135)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
11-14 16:50:22.199: E/WindowManager(22809):     at android.os.Handler.dispatchMessage(Handler.java:102)
**11-14 16:50:22.199: E/WindowManager(22809):   at android.os.Looper.loop(Looper.java:137)
11-14 16:50:22.199: E/WindowManager(22809):     at android.app.ActivityThread.main(ActivityThread.java:4998)
11-14 16:50:22.199: E/WindowManager(22809):     at java.lang.reflect.Method.invokeNative(Native Method)
11-14 16:50:22.199: E/WindowManager(22809):     at java.lang.reflect.Method.invoke(Method.java:515)
11-14 16:50:22.199: E/WindowManager(22809):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
11-14 16:50:22.199: E/WindowManager(22809):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
11-14 16:50:22.199: E/WindowManager(22809):     at dalvik.system.NativeStart.main(Native Method)

JsonParser: public class JSONParser {

    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";

    // constructor
    public JSONParser() {

    }

    // function get json from url
    // by making HTTP POST or GET mehtod
    public JSONObject makeHttpRequest(String url, String method,
            List<NameValuePair> params) {

        // Making HTTP request
        try {

            // check for request method
            if(method == "POST"){
                // request method is POST
                // defaultHttpClient
                DefaultHttpClient httpClient = new DefaultHttpClient();
                HttpPost httpPost = new HttpPost(url);
                httpPost.setEntity(new UrlEncodedFormEntity(params));

                HttpResponse httpResponse = httpClient.execute(httpPost);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();

            }else if(method == "GET"){
                // request method is GET
                DefaultHttpClient httpClient = new DefaultHttpClient();
                String paramString = URLEncodedUtils.format(params, "utf-8");
                url += "?" + paramString;
                HttpGet httpGet = new HttpGet(url);

                HttpResponse httpResponse = httpClient.execute(httpGet);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();
            }           

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        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();
            json = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }

        // return JSON String
        return jObj;

    }
}

SearchLocationAcitivity:

public class SearchLocationActivity extends ListActivity {

    // Progress Dialog
    private ProgressDialog pDialog;

    // Creating JSON Parser object
    JSONParser jParser = new JSONParser();

    ArrayList<HashMap<String, String>> productsList;

    // url to get all products list
    private static String url_all_products = "http://http://000100023.host56.com/db_all.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCTS = "locations";
    private static final String TAG_PID = "id";
    private static final String TAG_NAME = "name";

    // products JSONArray
    JSONArray products = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_search_location);

        // Hashmap for ListView
        productsList = new ArrayList<HashMap<String, String>>();

        // Loading products in Background Thread
        new LoadAllProducts().execute();

        // Get listview
        ListView lv = getListView();

        // on seleting single product
        // launching Edit Product Screen
        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // getting values from selected ListItem
                String pid = ((TextView) view.findViewById(R.id.pid)).getText()
                        .toString();

                // Starting new intent
                //Intent in = new Intent(getApplicationContext(),
                  //      EditProductActivity.class);
                // sending pid to next activity
                //in.putExtra(TAG_PID, pid);

                // starting new activity and expecting some response back
                //startActivityForResult(in, 100);
            }
        });

    }

    // Response from Edit Product Activity
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        // if result code 100
        if (resultCode == 100) {
            // if result code 100 is received
            // means user edited/deleted product
            // reload this screen again
            Intent intent = getIntent();
            finish();
            startActivity(intent);
        }

    }

    /**
     * Background Async Task to Load all product by making HTTP Request
     * */
    class LoadAllProducts extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(SearchLocationActivity.this);
            pDialog.setMessage("Loading locations. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(false);
            pDialog.show();
        }

        /**
         * getting All products from url
         * */
        protected String doInBackground(String... args) {
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            // getting JSON string from URL
            JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);

            // Check your log cat for JSON reponse
            Log.d("All Products: ", json.toString());

            try {
                // Checking for SUCCESS TAG
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    // products found
                    // Getting Array of Products
                    products = json.getJSONArray(TAG_PRODUCTS);

                    // looping through All Products
                    for (int i = 0; i < products.length(); i++) {
                        JSONObject c = products.getJSONObject(i);

                        // Storing each json item in variable
                        String id = c.getString(TAG_PID);
                        String name = c.getString(TAG_NAME);

                        // creating new HashMap
                        HashMap<String, String> map = new HashMap<String, String>();

                        // adding each child node to HashMap key => value
                        map.put(TAG_PID, id);
                        map.put(TAG_NAME, name);

                        // adding HashList to ArrayList
                        productsList.add(map);
                    }
                } else {
                    // no products found
                    // Launch Add New product Activity
                    //Intent i = new Intent(getApplicationContext(),
                      //      NewProductActivity.class);
                    // Closing all previous activities
                    //i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    //startActivity(i);
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog after getting all products
            pDialog.dismiss();
            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    /**
                     * Updating parsed JSON data into ListView
                     * */
                    ListAdapter adapter = new SimpleAdapter(
                            SearchLocationActivity.this, productsList,
                            R.layout.list_item, new String[] { TAG_PID,
                                    TAG_NAME},
                            new int[] { R.id.pid, R.id.name });
                    // updating listview
                    setListAdapter(adapter);
                }
            });

        }

    }
}

Any help is much appreciated!

Answer

your URL string is wrong, you wrote it like:

Private static String url_all_products = "http://http://000100023.host56.com/db_all.php";

it should be:

Private static String url_all_products = "http://000100023.host56.com/db_all.php";

one http:// is enough 😉

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