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java.lang.NullPointerException occuring, developing android, how do I fix that? [duplicate]

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What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 7 years ago.
java.lang.NullPointerException occuring
Log-cat says Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
Here's my code:
I'm trying to get jSon data from a server(MySql) database, then displaying it in a list.
public class AllProducts extends ListActivity {
private ProgressDialog pDialog;
JSONParser jParser=new JSONParser();
ArrayList<HashMap<String,String>> productsList;
private static String url_all_products = "http://server:host.../view.php";
private static final String TAG_SUCCESS="success";
private static final String TAG_PRODUCTS = "products";
private static final String TAG_PID = "pid";
private static final String TAG_NAME = "name";
JSONArray products=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_products);
productsList=new ArrayList<HashMap<String, String>>();
new LoadAllProducts().execute();
Exception at new LoadAllProducts().execute();
ListView lv = getListView();
}
class LoadAllProducts extends AsyncTask<String,String,String>
Java.lang.NullPointerException Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
occuring at class LoadAllProducts extends AsyncTask<String,String,String>
{
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog= new ProgressDialog(AllProducts.this);
pDialog.setMessage("Loading Products....Wait..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
Exception at pDialog.show();
}
#Override
protected String doInBackground(String... params) {
ContentValues param=new ContentValues();
JSONObject json= jParser.makeHttpRequest(url_all_products,"GET",param);
Log.d("All Products: ", json.toString());
java.lang.NullPointerException occuring at Log.d("All Products: ", json.toString());
try{
int success=json.getInt(TAG_SUCCESS);
if(success==1)
{
products = json.getJSONArray(TAG_PRODUCTS);
for(int j=0; j<products.length() ; j++ )
{
JSONObject c = products.getJSONObject(j);
String id=c.getString(TAG_PID);
String name=c.getString(TAG_NAME);
HashMap<String,String> map=new HashMap<String,String>();
map.put(TAG_PID,id);
map.put(TAG_NAME,name);
productsList.add(map);
}
}
else {
Intent i=new Intent(getApplicationContext(),NewProduct.class);
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
}
}catch(JSONException e)
{
e.printStackTrace();
}
return null;
}
}
}
I have a button in my UI to get data from server and show it in a list, as i tap the button, pDialog shows and then the app goes "not responding" and these exceptions occur
Here is the LogCat
09-03 16:10:40.500 27696-31923/com.example.vashisht.myapplication W/System.err﹕ at libcore.io.IoBridge.connectErrno(IoBridge.java:137)
09-03 16:10:40.500 27696-31923/com.example.vashisht.myapplication W/System.err﹕ at libcore.io.IoBridge.connect(IoBridge.java:122)
09-03 16:10:40.500 27696-31923/com.example.vashisht.myapplication W/System.err﹕ ... 19 more
09-03 16:10:40.500 27696-31923/com.example.vashisht.myapplication E/Buffer Error﹕ Error converting result java.lang.NullPointerException: lock == null
09-03 16:10:40.500 27696-31923/com.example.vashisht.myapplication E/JSON Parser﹕ Error parsing data org.json.JSONException: End of input at character 0 of
09-03 16:10:40.510 27696-31923/com.example.vashisht.myapplication E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: com.example.vashisht.myapplication, PID: 27696
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
at com.example.vashisht.myapplication.AllProducts$LoadAllProducts.doInBackground(AllProducts.java:76)
at com.example.vashisht.myapplication.AllProducts$LoadAllProducts.doInBackground(AllProducts.java:57)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)
09-03 16:10:40.980 27696-27696/com.example.vashisht.myapplication E/WindowManager﹕ android.view.WindowLeaked: Activity com.example.vashisht.myapplication.AllProducts has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{10a4b377 V.E..... R......D 0,0-1026,348} that was originally added here
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:382)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:261)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:298)
at com.example.vashisht.myapplication.AllProducts$LoadAllProducts.onPreExecute(AllProducts.java:67)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
at android.os.AsyncTask.execute(AsyncTask.java:535)
at com.example.vashisht.myapplication.AllProducts.onCreate(AllProducts.java:50)
at android.app.Activity.performCreate(Activity.java:5958)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1129)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2474)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1359)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5696)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1029)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:824)
09-03 16:10:44.250 27696-31923/com.example.vashisht.myapplication D/Process﹕ killProcess, pid=27696
09-03 16:10:44.260 27696-31923/com.example.vashisht.myapplication D/Process﹕ com.android.internal.os.RuntimeInit$UncaughtHandler.uncaughtException:138 java.lang.ThreadGroup.uncaughtException:693 java.lang.ThreadGroup.uncaughtException:690

this means that the JSONObject json == null. You can check this in code before calling methods on the JSONObject. I guess you dont actually get data when you call the httprequest.

App crashes when a button is clicked

I am trying to store the data entered by user to MySQL database using PHP in my android app. But whenever the button is clicked, i receive this message "Unfortunately, [app] has stopped working."
public class Register extends Activity implements View.OnClickListener {
private EditText userName, userContact, userAddress, userRequest;
private Spinner userStore;
private Button mRegister;
// Progress Dialog
private ProgressDialog pDialog;
// JSON parser class
JSONParser jsonParser = new JSONParser();
//php login script
//localhost :
//testing on your device
//put your local ip instead, on windows, run CMD > ipconfig
//or in mac's terminal type ifconfig and look for the ip under en0 or en1
// private static final String LOGIN_URL = "http://xxx.xxx.x.x:1234/webservice/register.php";
//testing on Emulator:
private static final String LOGIN_URL = "http://10.0.2.2/callarocket/register.php";
//testing from a real server:
//private static final String LOGIN_URL = "http://www.yourdomain.com/webservice/register.php";
//ids
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.first_screen);
Spinner dropdown = (Spinner)findViewById(R.id.StoreSpinner);
String[] items = new String[]{"NZ Mamak", "Indo Shop", "NZ Supermarket"};
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, items);
dropdown.setAdapter(adapter);
userName = (EditText)findViewById(R.id.EditName);
userContact = (EditText)findViewById(R.id.EditContact);
userAddress = (EditText)findViewById(R.id.EditAddress);
userStore = (Spinner)findViewById(R.id.StoreSpinner);
userRequest = (EditText)findViewById(R.id.EditRequest);
mRegister = (Button)findViewById(R.id.SubmitButton);
mRegister.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
new CreateUser().execute();
}
class CreateUser extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
boolean failure = false;
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Register.this);
pDialog.setMessage("Creating Request...");
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 = userName.getText().toString();
String usercontact = userContact.getText().toString();
String useraddress = userAddress.getText().toString();
String userstore = userStore.getSelectedItem().toString();
String userrequest = userRequest.getText().toString();
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("userName", username));
params.add(new BasicNameValuePair("userContact", usercontact));
params.add(new BasicNameValuePair("userAddress", useraddress));
params.add(new BasicNameValuePair("userStore", userstore));
params.add(new BasicNameValuePair("userRequest", userrequest));
Log.d("request!", "starting");
//Posting user data to script
JSONObject json = jsonParser.makeHttpRequest(
LOGIN_URL, "POST", params);
// full json response
Log.d("Login attempt", json.toString());
// json success element
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
Log.d("User Created!", json.toString());
finish();
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(Register.this, file_url, Toast.LENGTH_LONG).show();
}
}
}
}
And here is my JSONParser code.
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(final String url) {
// Making HTTP request
try {
// Construct the client and the HTTP request.
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
// Execute the POST request and store the response locally.
HttpResponse httpResponse = httpClient.execute(httpPost);
// Extract data from the response.
HttpEntity httpEntity = httpResponse.getEntity();
// Open an inputStream with the data content.
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
// Create a BufferedReader to parse through the inputStream.
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
// Declare a string builder to help with the parsing.
StringBuilder sb = new StringBuilder();
// Declare a string to store the JSON object data in string form.
String line = null;
// Build the string until null.
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
// Close the input stream.
is.close();
// Convert the string builder data to an actual string.
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// Try to 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 the JSON Object.
return jObj;
}
// 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;
}
}
And here is the logcat
02-25 11:25:36.224 2445-2460/com.example.user.callarocket D/OpenGLRenderer﹕ Render dirty regions requested: true
02-25 11:25:36.228 2445-2445/com.example.user.callarocket D/﹕ HostConnection::get() New Host Connection established 0xa6c43550, tid 2445
02-25 11:25:36.271 2445-2445/com.example.user.callarocket D/Atlas﹕ Validating map...
02-25 11:25:36.373 2445-2460/com.example.user.callarocket D/﹕ HostConnection::get() New Host Connection established 0xa6c438d0, tid 2460
02-25 11:25:36.423 2445-2460/com.example.user.callarocket I/OpenGLRenderer﹕ Initialized EGL, version 1.4
02-25 11:25:36.457 2445-2460/com.example.user.callarocket D/OpenGLRenderer﹕ Enabling debug mode 0
02-25 11:25:36.500 2445-2460/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 11:25:36.500 2445-2460/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xae1eb880, error=EGL_SUCCESS
02-25 11:25:48.014 2445-2460/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 11:25:48.014 2445-2460/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa5b6d2a0, error=EGL_SUCCESS
02-25 11:25:48.303 2445-2460/com.example.user.callarocket D/OpenGLRenderer﹕ endAllStagingAnimators on 0xa6cb7580 (RippleDrawable) with handle 0xa6c43c60
02-25 11:25:59.147 2445-2465/com.example.user.callarocket D/request!﹕ starting
02-25 11:25:59.207 2445-2460/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 11:25:59.207 2445-2460/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xae1f3be0, error=EGL_SUCCESS
02-25 11:25:59.281 2445-2465/com.example.user.callarocket E/JSON Parser﹕ Error parsing data org.json.JSONException: Value Posted of type java.lang.String cannot be converted to JSONObject
02-25 11:25:59.299 2445-2465/com.example.user.callarocket E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: com.example.user.callarocket, PID: 2445
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
at com.example.user.callarocket.Register$CreateUser.doInBackground(Register.java:128)
at com.example.user.callarocket.Register$CreateUser.doInBackground(Register.java:85)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)
02-25 11:25:59.599 2445-2460/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 11:25:59.599 2445-2460/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xae1f3e60, error=EGL_SUCCESS
02-25 11:26:00.172 2445-2445/com.example.user.callarocket E/WindowManager﹕ android.view.WindowLeaked: Activity com.example.user.callarocket.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{2dbde5f6 V.E..... R......D 0,0-1026,348} that was originally added here
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:363)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:261)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:298)
at com.example.user.callarocket.Register$CreateUser.onPreExecute(Register.java:99)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
at android.os.AsyncTask.execute(AsyncTask.java:535)
at com.example.user.callarocket.Register.onClick(Register.java:81)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
After Log.i("DATA",json) is added
02-25 12:24:16.222 2750-2765/com.example.user.callarocket D/OpenGLRenderer﹕ Render dirty regions requested: true
02-25 12:24:16.225 2750-2750/com.example.user.callarocket D/﹕ HostConnection::get() New Host Connection established 0xa6c3e550, tid 2750
02-25 12:24:16.259 2750-2750/com.example.user.callarocket D/Atlas﹕ Validating map...
02-25 12:24:16.366 2750-2765/com.example.user.callarocket D/﹕ HostConnection::get() New Host Connection established 0xa6c3e6f0, tid 2765
02-25 12:24:16.405 2750-2765/com.example.user.callarocket I/OpenGLRenderer﹕ Initialized EGL, version 1.4
02-25 12:24:16.433 2750-2765/com.example.user.callarocket D/OpenGLRenderer﹕ Enabling debug mode 0
02-25 12:24:16.462 2750-2765/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 12:24:16.462 2750-2765/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa6c118a0, error=EGL_SUCCESS
02-25 12:24:24.841 2750-2765/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 12:24:24.842 2750-2765/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa5e39720, error=EGL_SUCCESS
02-25 12:24:25.095 2750-2765/com.example.user.callarocket D/OpenGLRenderer﹕ endAllStagingAnimators on 0xa6cb2580 (RippleDrawable) with handle 0xa6c3eab0
02-25 12:24:33.820 2750-2768/com.example.user.callarocket D/request!﹕ starting
02-25 12:24:33.862 2750-2765/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 12:24:33.863 2750-2765/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa5605140, error=EGL_SUCCESS
02-25 12:24:34.027 2750-2768/com.example.user.callarocket E/JSON Parser﹕ Error parsing data org.json.JSONException: Value Posted of type java.lang.String cannot be converted to JSONObject
02-25 12:24:34.028 2750-2768/com.example.user.callarocket E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: com.example.user.callarocket, PID: 2750
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
at com.example.user.callarocket.Register$CreateUser.doInBackground(Register.java:128)
at com.example.user.callarocket.Register$CreateUser.doInBackground(Register.java:85)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)
02-25 12:24:34.335 2750-2765/com.example.user.callarocket W/EGL_emulation﹕ eglSurfaceAttrib not implemented
02-25 12:24:34.335 2750-2765/com.example.user.callarocket W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xa5af7e00, error=EGL_SUCCESS
02-25 12:24:36.361 2750-2750/com.example.user.callarocket I/Choreographer﹕ Skipped 106 frames! The application may be doing too much work on its main thread.
02-25 12:24:36.754 2750-2750/com.example.user.callarocket E/WindowManager﹕ android.view.WindowLeaked: Activity com.example.user.callarocket.Register has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{2dbde5f6 V.E..... R......D 0,0-1026,348} that was originally added here
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:363)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:261)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:298)
at com.example.user.callarocket.Register$CreateUser.onPreExecute(Register.java:99)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
at android.os.AsyncTask.execute(AsyncTask.java:535)
at com.example.user.callarocket.Register.onClick(Register.java:81)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

You have problem in.
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
new CreateUser().execute();
}
here you have to use which button is clicked. normally we use
switch(v.getId())
{
case your button id :
//Button function
}

You need to be using a parser to parse the string and then cast it to a JSONObject like so -
JSONParser parser = new JSONParser();
Object obj = parser.parse(json);
JSONObject jsonObj = (JSONObject) obj;
return jsonObj;

Uploading images to remote MySQL server

Good day. Please can someone help me with this?
Is it possible to upload images from android to remote database?
I'm able to communicate with my remote database and perform simple operations like read, write, and delete from database but I have a problem when it comes to uploading images. I'v spent my whole day searching trying and reading methods to accomplish this from stackoverflow and other websites.
This is what I have tried
public class MainActivity extends Activity {
Bitmap bitmap1;
byte[]image1byte;
...
#Override
protected void onActivityResult(int requestCode,int resultCode,Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == PICK_IMAGE_1) {
Uri selectedImage = data.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String picturePath = cursor.getString(columnIndex);
cursor.close();
bitmap1 = BitmapFactory.decodeFile(picturePath);
image1 = (ImageView) findViewById(R.id.imageView1);
image1.setImageBitmap(bitmap1);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap1.compress(Bitmap.CompressFormat.JPEG,100,stream);
image1byte=stream.toByteArray();
}
and my AsyncTask task is;
class CreateNewMessage extends AsyncTask<String,String,String>{
#Override
protected void onPreExecute(){
pDialog=new ProgressDialog(MainActivity.this);
pDialog.setMessage("Uploading Message...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected String doInBackground(String... strings) {
String topic=inputTopic.getText().toString();
String message=inputMessage.getText().toString();
String other=inputOther.getText().toString();
List<NameValuePair>params=new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("topic",topic));
params.add(new BasicNameValuePair("message",message));
params.add(new BasicNameValuePair("details",details));
params.add(new BasicNameValuePair("image",sendImage1));
JSONObject json=jsonParser.makeHttpRequest(url_create_message,"GET",params);
try {
response=json.getString(TAG_SUCCESS);
} catch (JSONException e) {
e.printStackTrace();
}
Log.d("Response",json.toString());
return response;
}
protected void onPostExecute(String response) {
Toast.makeText(getBaseContext(),"Finished..Response= "+response,Toast.LENGTH_LONG).show();
pDialog.dismiss();
}
}
but I get the following error;
12-12 16:22:47.017 15942-15985/com.example.mcleroy.studentboxadminpanel E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #3
Process: com.example.mcleroy.studentboxadminpanel, PID: 15942
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.example.mcleroy.studentboxadminpanel.MainActivity$CreateNewMessage.doInBackground(MainActivity.java:119)
at com.example.mcleroy.studentboxadminpanel.MainActivity$CreateNewMessage.doInBackground(MainActivity.java:96)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
12-12 16:22:48.286 15942-15942/com.example.mcleroy.studentboxadminpanel E/WindowManager﹕ android.view.WindowLeaked: Activity com.example.mcleroy.studentboxadminpanel.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{4261d878 V.E..... R......D 0,0-684,192} that was originally added here
at android.view.ViewRootImpl.(ViewRootImpl.java:376)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:286)
at com.example.mcleroy.studentboxadminpanel.MainActivity$CreateNewMessage.onPreExecute(MainActivity.java:104)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
at android.os.AsyncTask.execute(AsyncTask.java:535)
at com.example.mcleroy.studentboxadminpanel.MainActivity.createMessage(MainActivity.java:94)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at android.view.View$1.onClick(View.java:3846)
at android.view.View.performClick(View.java:4466)
at android.view.View$PerformClick.run(View.java:18537)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5102)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:132)
at dalvik.system.NativeStart.main(Native Method)
Please please can anyone look into my code and tell me what I am not doing write, as I really need to be able to upload and download images from my app to remote database nd from remote database to app respectively. or is it impossible to accomplish this?
Here is my PHP script
<?php
$servername = "xxxxx";
$username = "xxxxx";
$password = "xxxxx";
$dbname = "xxxxx";
$response = array();
$topic = $_GET['name'];
$message = $_GET['price'];
$details = $_GET['description'];
$image=$_GET['image'];
$con = mysql_connect($servername,$username,$password) or die(mysql_error());
mysql_select_db($dbname) or die(mysql_error());
$result = mysql_query("INSERT INTO messages(topic, messages, others,image) VALUES('$name', '$price',`` '$description','$image')");
if ($result) {
// successfully inserted into database
$response["success"] = 1;
$response["message"] = "Message successfully created.";
// echoing JSON response
echo json_encode($response);
}
?>
Thanks alot in advance as you try to help;

AsyncTask error occured while executing doInBackground()

I'm getting an error in following code, calling asyn method for http request. It gives me a java.lang.RuntimeException error inside doInBackground() method.
_____________MAIN class____________
TextView testoInput = (TextView) findViewById(R.id.input);
final String località = testoInput.getText().toString();
bottone1.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
TaskAsincrono nuovo = new TaskAsincrono();
nuovo.execute(località);
}
__________ASYNC Class________
public class TaskAsincrono extends AsyncTask > {
protected ArrayList<String> doInBackground(String...params) {
String s = params[0];
ArrayList<String> risultato =null;
//Inizio sessione di invio dati rest con sistema GET
DefaultHttpClient client = new DefaultHttpClient();
String url ="http://www.replycoupon.it/php/rest_Server/index.php?nome="+s;
try {
URI uri = new URI(url);
HttpGet get = new HttpGet(uri);
HttpResponse res = client.execute(get);
InputStream data = res.getEntity().getContent();
//Inizio l'operazione di buffering per la lettura
BufferedReader streamReader = new BufferedReader(new InputStreamReader(data));
StringBuilder responseStrBuilder = new StringBuilder();
String inputStr =null;
while ((inputStr = streamReader.readLine()) != null)
responseStrBuilder.append(inputStr);
JSONObject jObj = new JSONObject(responseStrBuilder.toString());
String clima = jObj.getString("clima");
String temperatura = jObj.getString("temperatura");
//Prima di inviare alla main metto il risultato in un arrylist
risultato.add(clima);
risultato.add(temperatura);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (URISyntaxException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return risultato;
}
protected void onPostExecute(final ArrayList<String> risultato) {
final TextView testoClima = (TextView) findViewById(R.id.Output);
final TextView testoTemp = (TextView) findViewById(R.id.Output2);
testoClima.setText(risultato.get(0).toString());
testoTemp.setText(risultato.get(1).toString());
}
}
LOG
10-02 20:53:07.068: D/dalvikvm(4050): GC_FOR_ALLOC freed 234K, 4% free 7914K/8188K, paused 16ms, total 16ms
10-02 20:53:09.728: W/dalvikvm(4050): threadid=11: thread exiting with uncaught exception (group=0x41800ba8)
10-02 20:53:09.728: E/AndroidRuntime(4050): FATAL EXCEPTION: AsyncTask #1
10-02 20:53:09.728: E/AndroidRuntime(4050): Process: luca.tirocinio.client_json, PID: 4050
10-02 20:53:09.728: E/AndroidRuntime(4050): java.lang.RuntimeException: An error occured while executing doInBackground()
10-02 20:53:09.728: E/AndroidRuntime(4050): at android.os.AsyncTask$3.done(AsyncTask.java:300)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.FutureTask.run(FutureTask.java:242)
10-02 20:53:09.728: E/AndroidRuntime(4050): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.lang.Thread.run(Thread.java:841)
10-02 20:53:09.728: E/AndroidRuntime(4050): Caused by: java.lang.NullPointerException
10-02 20:53:09.728: E/AndroidRuntime(4050): at luca.tirocinio.client_json.MainActivity$TaskAsincrono.doInBackground(MainActivity.java:117)
10-02 20:53:09.728: E/AndroidRuntime(4050): at luca.tirocinio.client_json.MainActivity$TaskAsincrono.doInBackground(MainActivity.java:1)
10-02 20:53:09.728: E/AndroidRuntime(4050): at android.os.AsyncTask$2.call(AsyncTask.java:288)
10-02 20:53:09.728: E/AndroidRuntime(4050): at java.util.concurrent.FutureTask.run(FutureTask.java:237)
10-02 20:53:09.728: E/AndroidRuntime(4050): ... 4 more
10-02 20:53:13.768: I/Process(4050): Sending signal. PID: 4050 SIG: 9

You're trying to add results to ArrayList<String> risultato which is null. Just replace it with ArrayList<String> risultato = new ArrayList<String>();

Error parsing data org.json.JSONException: Value <br with a login system android

I want to make a login registration system with my app but is not working properly. Here the code where I think I've got an error.
PHP LOGIN SCRIPT :
<?php
//load and connect to MySQL database stuff
require("config.inc.php");
if (!empty($_POST)) {
//gets user's info based off of a username.
$query = "
SELECT
id,
username,
password
FROM users
WHERE
username = :username
";
$query_params = array(
':username' => $_POST['username']
);
try {
$stmt = $db->prepare($query);
$result = $stmt->execute($query_params);
}
catch (PDOException $ex) {
// For testing, you could use a die and message.
//die("Failed to run query: " . $ex->getMessage());
//or just use this use this one to product JSON data:
$response["success"] = 0;
$response["message"] = "Database Error1. Please Try Again!";
die(json_encode($response));
}
//This will be the variable to determine whether or not the user's information is correct.
//we initialize it as false.
$validated_info = false;
//fetching all the rows from the query
$row = $stmt->fetch();
if ($row) {
//if we encrypted the password, we would unencrypt it here, but in our case we just
//compare the two passwords
if ($_POST['password'] === $row['password']) {
$login_ok = true;
}
}
// If the user logged in successfully, then we send them to the private members-only page
// Otherwise, we display a login failed message and show the login form again
if ($login_ok) {
$response["success"] = 1;
$response["message"] = "Login successful!";
die(json_encode($response));
} else {
$response["success"] = 0;
$response["message"] = "Invalid Credentials!";
die(json_encode($response));
}
} else {
$response["message"] = "Enter username and password!";
die(json_encode($response));
}
?>
<h1>Login</h1>
<form action="login.php" method="post">
Username:<br />
<input type="text" name="username" placeholder="username" />
<br /><br />
Password:<br />
<input type="password" name="password" placeholder="password" value="" />
<br /><br />
<input type="submit" value="Login" />
</form>
Register
<?php
?>
LoginActivity :
public class LoginActivity extends ActionBarActivity {
Button btnLogin;
Button btnLinkToRegister;
EditText inputEmail;
EditText inputPassword;
TextView loginErrorMsg;
private ProgressDialog pDialog;
JSONParser jsonParser = new JSONParser();
// JSON Response node names
private static String KEY_SUCCESS = "success";
private static String KEY_ERROR = "error";
private static String KEY_ERROR_MSG = "error_msg";
private static String KEY_UID = "uid";
private static String KEY_NAME = "name";
private static String KEY_EMAIL = "email";
private static String KEY_CREATED_AT = "created_at";
private static final String TAG_MESSAGE = "message";
// Testing on emulator
private static String LOGIN_URL = "http://10.0.2.2/webservice/login.php";
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
getSupportActionBar().hide();
setContentView(R.layout.login);
// Importing all assets like buttons, text fields
inputEmail = (EditText) findViewById(R.id.loginEmail);
inputPassword = (EditText) findViewById(R.id.loginPassword);
btnLogin = (Button) findViewById(R.id.btnLogin);
btnLinkToRegister = (Button) findViewById(R.id.btnLinkToRegisterScreen);
loginErrorMsg = (TextView) findViewById(R.id.login_error);
// Login button Click Event
btnLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
new LoginProcess().execute();
}
});
// Link to Register Screen
btnLinkToRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
RegisterActivity.class);
startActivity(i);
finish();
}
});
}
private class LoginProcess extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(LoginActivity.this);
pDialog.setMessage("Attempting login...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected String doInBackground(String... args) {
// Check for success tag
int success;
String username = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
try {
// 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);
// check your log for json response
Log.d("Login attempt", json.toString());
// json success tag
success = json.getInt(KEY_SUCCESS);
if (success == 1) {
Log.d("Login Successful!", json.toString());
Intent i = new Intent(LoginActivity.this,
MainActivity.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(LoginActivity.this, file_url, Toast.LENGTH_LONG).show();
}
}
}
}
JSONParser Class:
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {
// Making HTTP request
try {
// 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();
} 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();
Log.e("JSON", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
Log.d("JSON Parser", json);
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
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;
}
}
When I want to login with the right username and password it's working but if I put right username and wrong password I've got an error. But if I delete query_params at :
$result = $stmt->execute($query_params);
I don't have any errors but I can't login anymore
The logcat :
08-31 10:40:39.885: E/Trace(1239): error opening trace file: No such file or directory (2)
08-31 10:40:40.785: D/dalvikvm(1239): GC_FOR_ALLOC freed 118K, 2% free 10936K/11143K, paused 55ms, total 57ms
08-31 10:40:40.845: I/dalvikvm-heap(1239): Grow heap (frag case) to 13.346MB for 2764816-byte allocation
08-31 10:40:40.954: D/dalvikvm(1239): GC_CONCURRENT freed 1K, 2% free 13635K/13895K, paused 24ms+6ms, total 108ms
08-31 10:40:41.334: D/libEGL(1239): loaded /system/lib/egl/libEGL_emulation.so
08-31 10:40:41.345: D/(1239): HostConnection::get() New Host Connection established 0x2a126450, tid 1239
08-31 10:40:41.357: D/libEGL(1239): loaded /system/lib/egl/libGLESv1_CM_emulation.so
08-31 10:40:41.376: D/libEGL(1239): loaded /system/lib/egl/libGLESv2_emulation.so
08-31 10:40:41.455: W/EGL_emulation(1239): eglSurfaceAttrib not implemented
08-31 10:40:41.465: D/OpenGLRenderer(1239): Enabling debug mode 0
08-31 10:40:45.545: D/request!(1239): starting
08-31 10:40:45.645: W/EGL_emulation(1239): eglSurfaceAttrib not implemented
08-31 10:40:48.205: E/JSON Parser(1239): Error parsing data org.json.JSONException: Value <br of type java.lang.String cannot be converted to JSONObject
08-31 10:40:48.355: W/dalvikvm(1239): threadid=11: thread exiting with uncaught exception (group=0x40a13300)
08-31 10:40:48.754: E/AndroidRuntime(1239): FATAL EXCEPTION: AsyncTask #1
08-31 10:40:48.754: E/AndroidRuntime(1239): java.lang.RuntimeException: An error occured while executing doInBackground()
08-31 10:40:48.754: E/AndroidRuntime(1239): at android.os.AsyncTask$3.done(AsyncTask.java:299)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
08-31 10:40:48.754: E/AndroidRuntime(1239): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.lang.Thread.run(Thread.java:856)
08-31 10:40:48.754: E/AndroidRuntime(1239): Caused by: java.lang.NullPointerException
08-31 10:40:48.754: E/AndroidRuntime(1239): at com.example.diycenter.LoginActivity$LoginProcess.doInBackground(LoginActivity.java:118)
08-31 10:40:48.754: E/AndroidRuntime(1239): at com.example.diycenter.LoginActivity$LoginProcess.doInBackground(LoginActivity.java:1)
08-31 10:40:48.754: E/AndroidRuntime(1239): at android.os.AsyncTask$2.call(AsyncTask.java:287)
08-31 10:40:48.754: E/AndroidRuntime(1239): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
08-31 10:40:48.754: E/AndroidRuntime(1239): ... 5 more
08-31 10:40:51.844: E/WindowManager(1239): Activity com.example.diycenter.LoginActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView#4148a190 that was originally added here
08-31 10:40:51.844: E/WindowManager(1239): android.view.WindowLeaked: Activity com.example.diycenter.LoginActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView#4148a190 that was originally added here
08-31 10:40:51.844: E/WindowManager(1239): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:374)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:292)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.Window$LocalWindowManager.addView(Window.java:547)
08-31 10:40:51.844: E/WindowManager(1239): at android.app.Dialog.show(Dialog.java:277)
08-31 10:40:51.844: E/WindowManager(1239): at com.example.diycenter.LoginActivity$LoginProcess.onPreExecute(LoginActivity.java:96)
08-31 10:40:51.844: E/WindowManager(1239): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
08-31 10:40:51.844: E/WindowManager(1239): at android.os.AsyncTask.execute(AsyncTask.java:534)
08-31 10:40:51.844: E/WindowManager(1239): at com.example.diycenter.LoginActivity$1.onClick(LoginActivity.java:69)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.View.performClick(View.java:4084)
08-31 10:40:51.844: E/WindowManager(1239): at android.view.View$PerformClick.run(View.java:16966)
08-31 10:40:51.844: E/WindowManager(1239): at android.os.Handler.handleCallback(Handler.java:615)
08-31 10:40:51.844: E/WindowManager(1239): at android.os.Handler.dispatchMessage(Handler.java:92)
08-31 10:40:51.844: E/WindowManager(1239): at android.os.Looper.loop(Looper.java:137)
08-31 10:40:51.844: E/WindowManager(1239): at android.app.ActivityThread.main(ActivityThread.java:4745)
08-31 10:40:51.844: E/WindowManager(1239): at java.lang.reflect.Method.invokeNative(Native Method)
08-31 10:40:51.844: E/WindowManager(1239): at java.lang.reflect.Method.invoke(Method.java:511)
08-31 10:40:51.844: E/WindowManager(1239): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
08-31 10:40:51.844: E/WindowManager(1239): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-31 10:40:51.844: E/WindowManager(1239): at dalvik.system.NativeStart.main(Native Method)

The OP wrote in an edit:
UPDATE : I found the solution I add :
Log.e("jsonlol", json);
in the JSONParser class before i create the JSONObject and then i check in the logcat what was the the message and it was like that :
08-31 12:31:16.854: E/jsonlol(786): <br />
08-31 12:31:16.854: E/jsonlol(786): <b>Notice</b>: Undefined variable: login_ok in <b>C:\xampp\htdocs\webservice\login.php</b> on line <b>54</b><br />
08-31 12:31:16.854: E/jsonlol(786): {"success":0,"message":"Invalid Credentials!"}
08-31 12:31:17.012: E/JSON Parser(786): Error parsing data org.json.JSONException: Value <br of type java.lang.String cannot be converted to JSONObject
So I went to the php file login.php on line 54 and there was a variable name problem I just change
$validated_info = false;
by
$login_ok = false;
If you follow the mybringback tutorial it's an error on the script.