Fatal Exception AsyncTask #1 and Android doInBackground()

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Good morning StackOver Flow Pros,

I need a little help here. I am running an Android application which calls out to a MySql database via a php script, When I run the application I get a Fatal Exception error for AsyncTask #1 caused by, a null pointer exception. It said it occurred while executing doInBackground. This is a tutorial I am following from MyBringBack. I really need to wrap my head around this because I have been trying to figure this out for days. If I remove/comment most of the Log.d statements it will run fine but I will not see the tags for what is going on from the JSON responses, the code is listed below, could anyone help me figure this out or tell me what is wrong with the code.

Here is the error log from logcat

10-25 09:27:47.818: E/JSON Parser(1041): Error parsing data org.json.JSONException: Value array(2) of type java.lang.String cannot be converted to JSONObject 10-25 09:27:47.818: W/dalvikvm(1041): threadid=11: thread exiting with uncaught exception (group=0xb1b06ba8) 10-25 09:27:47.828: E/AndroidRuntime(1041): FATAL EXCEPTION: AsyncTask #1 10-25 09:27:47.828: E/AndroidRuntime(1041): Process: com.bobcatservice, PID: 1041 10-25 09:27:47.828: E/AndroidRuntime(1041): java.lang.RuntimeException: An error occured while executing doInBackground() 10-25 09:27:47.828: E/AndroidRuntime(1041): at android.os.AsyncTask$3.done(AsyncTask.java:300) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.FutureTask.setException(FutureTask.java:222) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.FutureTask.run(FutureTask.java:242) 10-25 09:27:47.828: E/AndroidRuntime(1041): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.lang.Thread.run(Thread.java:841) 10-25 09:27:47.828: E/AndroidRuntime(1041): Caused by: java.lang.NullPointerException 10-25 09:27:47.828: E/AndroidRuntime(1041): at com.bobcatservice.Login$AttemptLogin.doInBackground(Login.java:126) 10-25 09:27:47.828: E/AndroidRuntime(1041): at com.bobcatservice.Login$AttemptLogin.doInBackground(Login.java:1) 10-25 09:27:47.828: E/AndroidRuntime(1041): at android.os.AsyncTask$2.call(AsyncTask.java:288) 10-25 09:27:47.828: E/AndroidRuntime(1041): at java.util.concurrent.FutureTask.run(FutureTask.java:237) 10-25 09:27:47.828: E/AndroidRuntime(1041): ... 4 more 10-25 09:27:49.968: E/WindowManager(1041): android.view.WindowLeaked: Activity com.bobcatservice.Login has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b1e8e430 V.E..... R......D 0,0-684,192} that was originally added here 10-25 09:27:49.968: E/WindowManager(1041): at android.view.ViewRootImpl.(ViewRootImpl.java:348) 10-25 09:27:49.968: E/WindowManager(1041): at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248) 10-25 09:27:49.968: E/WindowManager(1041): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69) 10-25 09:27:49.968: E/WindowManager(1041): at android.app.Dialog.show(Dialog.java:286)

And here is the code in question

//AsyncTask is a seperate thread than the thread that runs the GUI
//Any type of networking should be done with asynctask.
class AttemptLogin extends AsyncTask<String, String, String> {
    * Before starting background thread Show Progress Dialog
    boolean failure = false;
   @Override
   protected void onPreExecute() {
       super.onPreExecute();
       pDialog = new ProgressDialog(Login.this);
       pDialog.setMessage("Attempting login...");
       pDialog.setIndeterminate(false);
       pDialog.setCancelable(true);
       pDialog.show();
    @Override
    protected String doInBackground(String... args) {
        // TODO Auto-generated method stub
         // Check for success tag
       int success;
       String username = user.getText().toString();
       String password = pass.getText().toString();
           // Building Parameters
           List<NameValuePair> params = new ArrayList<NameValuePair>();
           params.add(new BasicNameValuePair("username", username));
           params.add(new BasicNameValuePair("password", password));
           Log.d("request!", "starting");
           // getting product details by making HTTP request
           JSONObject json = jsonParser.makeHttpRequest(
                  LOGIN_URL, "POST", params);
           try {
           // check your log for json response
           Log.d("Login attempt", json.toString());
           // json success tag
           success = json.getInt(TAG_SUCCESS);
           if (success == 1) {
            Log.d("Login Successful!", json.toString());
            Intent i = new Intent(Login.this, Welcome.class);
            finish();
            startActivity(i);
            return json.getString(TAG_MESSAGE);
            }else{
            Log.d("Login Failure!", json.getString(TAG_MESSAGE));
            return json.getString(TAG_MESSAGE);
        } catch (JSONException e) {
           e.printStackTrace();
       return null;
    * After completing background task Dismiss the progress dialog
    * **/
   protected void onPostExecute(String file_url) {
       // dismiss the dialog once product deleted
       pDialog.dismiss();
       if (file_url != null){
        Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
It seems like we can find an issue in some of your log invocations in doInBackground() method. What about this one?  
Log.d("request!", "starting");
No, seems good. What about the next one?
Log.d("Login attempt", json.toString());
Aha! How do we get this json variable?
JSONObject json = jsonParser.makeHttpRequest(LOGIN_URL, "POST", params);
Check the result of your http request, you probably get null here.
What if json is not null? Well, we have another suspicious log call:  
Log.d("Login Failure!", json.getString(TAG_MESSAGE));
As far as I remember, if the second argument of Log.d() is null, you're getting NullPointerException, so check this one too.  
What if it isn't an issue either? Well, I suggest you use debugger here.
                Hi aga, whenI went into debug mode, I set a breakpoint at the statement JSONObject json = jsonParser.makeHttpRequest(Login_URL, "POST", params); and after I step over the statement the json result is null, not sure what the problem is.
– Psy Chotic
                Oct 25, 2014 at 14:10
                Thanks aga, after cyphering through, and reading reading thoroughly your comment, I went back to my php file and found the problem was within the script, I had some var dumps that was outputting information that was screwing the JSON up
– Psy Chotic
                Oct 25, 2014 at 18:59
on top of ur code pls check create_product.php exists (here in android folder) and replace table_name with your table name and make $response["message"] =  mysql_error(); to know what is wrong with create_product.php in logcat of android sdk
// url to create send data. This contains the ip address of my machine on which the local server is running. You will write the IP address of your machine
         private static String url = "http://192.168.***.1:8080/android/create_product.php";
create_product.php 
// array for JSON response
$response = array();
// check for required fields
if (isset($_POST['id']) && isset($_POST['name'])) { 
$id = $_POST['id'];
$name = $_POST['name'];   
// include db connect class
require_once __DIR__ . '/db_connect.php'; 
// connecting to db
$db = new DB_CONNECT(); 
// mysql inserting a new row
$result = mysql_query("INSERT INTO table_name(id, name) VALUES('$id', '$name')"); 
// check if row inserted or not
if ($result) {
// successfully inserted into database
$response["success"] = 1;
$response["message"] = "Product successfully created."; 
// echoing JSON response
echo json_encode($response);
} else {
// failed to insert row
$response["success"] = 0;
$response["message"] =  mysql_error();; 
// echoing JSON response
echo json_encode($response);
} else {
// required field is missing
$response["success"] = 0;
$response["message"] = "Required field(s) is missing"; 
// echoing JSON response
echo json_encode($response);
And also add in manifest this code else this error will generate
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
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