Comment résoudre java.lang.RuntimeException erreur s'est produite lors de l'exécution de doInBackground()?

Je suis débutant en développement android, j'obtiens l'erreur dans le code suivant. Je fais appel asyn méthode de requête http, avant que je vérifie Wifi ou Réseau Mobile est disponible ou pas. Quand la connexion Internet est disponible Mon Service est en cours d'exécution fine, mais quand hors ligne en mode ma je obtenir ce type d'erreur:
"de java.lang.RuntimeException: Une erreur s'est produite lors de l'exécution de doInBackground()"

04-09 19:44:33.057: E/AndroidRuntime(3127): FATAL EXCEPTION: AsyncTask #1
04-09 19:44:33.057: E/AndroidRuntime(3127): java.lang.RuntimeException: An error      occured while executing doInBackground()
04-09 19:44:33.057: E/AndroidRuntime(3127):     at   android.os.AsyncTask$3.done(AsyncTask.java:278)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.lang.Thread.run(Thread.java:856)
04-09 19:44:33.057: E/AndroidRuntime(3127): Caused by: java.lang.NullPointerException
04-09 19:44:33.057: E/AndroidRuntime(3127):     at com.zoomi_zdc.SERVICES.MyServiceProf$myPostData.doInBackground(MyServiceProf.java:129)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at com.zoomi_zdc.SERVICES.MyServiceProf$myPostData.doInBackground(MyServiceProf.java:1)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at android.os.AsyncTask$2.call(AsyncTask.java:264)
04-09 19:44:33.057: E/AndroidRuntime(3127):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)

Ci-dessous est MyServiceProfile code. Dans ce code je suis vérification de la connectivité Internet et l'aftr tht Si l'Utilisateur est hors ligne, les données enregistrées dans la base de données locale et au cours de la Connexion Internet automatiquement mise à Jour sur notre serveur

public class MyServiceProf extends Service {
Timer t = new Timer();
public TimerTask mTimerTask;
private ConnectivityManager connectivityManager;
final Handler handler = new Handler();
private int nCounter = 0;
Context context = this;
@Override
public IBinder onBind(Intent intent) {
//TODO Auto-generated method stub
return null;
}
public void onCreate() {
}
@Override
public void onStart(Intent intent, int startId) {
//TODO Auto-generated method stub
mTimerTask = new TimerTask() {
public void run() {
handler.post(new Runnable() {
public void run() {
nCounter++;
connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
final android.net.NetworkInfo wifi = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
final android.net.NetworkInfo mobile = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (wifi.isAvailable()) {
mTimerTask.cancel();
try{
new myPostData().execute();
}catch (Exception e) {
//TODO: handle exception
}
} else if (mobile.isAvailable()) {
mTimerTask.cancel();
try{
new myPostData().execute();
}catch (Exception e) {
//TODO: handle exception
}
} else {
// Toast.makeText(getBaseContext(),"You are trying to access online content but Internet Connection has been disconnected!!!",Toast.LENGTH_SHORT).show();
}
}
});
Log.d("TIMER", "TimerTask run");
}
};
//public void schedule (TimerTask task, long delay, long period)
t.schedule(mTimerTask, 0, 10000); //
}
@Override
public void onDestroy() {
//TODO Auto-generated method stub
try {
t.cancel();
handler.removeCallbacks(mTimerTask);
} catch (Exception e) {
//TODO: handle exception
}
// Toast.makeText(getApplicationContext(), " Stopped", Toast.LENGTH_SHORT).show();
}
public class myPostData extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
//TODO Auto-generated method stub
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
//TODO Auto-generated method stub
HttpProfilePost proupdate = new HttpProfilePost();
String mMyprofileImagename[] = DatabaseHalper.mStudentImgNm.get(0).split("/");
File sdcardPathofprofileimg = new File(Environment.getExternalStorageDirectory()+"/data/.System/MProfile/" +mMyprofileImagename[1]);
Bitmap mBitmapimageofMyProfilepic = BitmapFactory.decodeFile(sdcardPathofprofileimg.getAbsolutePath());
DatabaseHalper dbhelper = new DatabaseHalper(getBaseContext());
dbhelper.Get_ZoomiProfile_Data();
proupdate.HttpClient_Profile_Post(context,DatabaseHalper.mStudentRollNo.get(0),
DatabaseHalper.mStudentName.get(0),
DatabaseHalper.mStudentAddress.get(0),
DatabaseHalper.mStudentEmrg_Person.get(0),
DatabaseHalper.mStudentEmrg_No.get(0),
DatabaseHalper.mStudentEmail.get(0),
DatabaseHalper.mStudentBloodGrp.get(0),
DatabaseHalper.mStudentMobileno.get(0),
mBitmapimageofMyProfilepic);
return null;
}
@Override
protected void onPostExecute(Void result) {
//TODO Auto-generated method stub
super.onPostExecute(result);
}
}

}

Ma mise à Jour sur le serveur Http code de lien est ci-dessous:

public class HttpProfilePost {
private JSONObject jsonResponse;
private Bitmap myPic;
private ByteArrayOutputStream bos;
private byte[] data;
/*private ByteArrayBody bab;
private MultipartEntity reqEntity;*/
private InputStream is;
private SharedPreferences mPref;
private SharedPreferences.Editor mEditor;
private Context mContext;
private HttpResponse httpResp;
List<String> a;
private String image1,image2,image3,image4,image5,image6,image7,image8,image9,image10;
//private String WEBSERVICE_NAME = "Profile_post.aspx";
public JSONObject HttpClient_Profile_Post(Context c,String stud_rollno, String stud_name,String stud_address, String stud_emrgperson, String stud_emrgcontact, String stud_email, String stud_bloodgrp, String stud_mobileno, Bitmap myPhoto){
mContext=c;
mPref = PreferenceManager.getDefaultSharedPreferences(mContext);
HttpClient httpClient = new DefaultHttpClient();
String mStudentUserid= mPref.getString("Userid", "" );
String myImage[] = DatabaseHalper.mStudentImgNm.get(0).split("/");
String profileimagepath = myImage[0];
stud_name = URLEncoder.encode(stud_name);
stud_address = URLEncoder.encode(stud_address);
stud_emrgperson = URLEncoder.encode(stud_emrgperson);
stud_emrgcontact = URLEncoder.encode(stud_emrgcontact);
stud_email = URLEncoder.encode(stud_email);
stud_bloodgrp = URLEncoder.encode(stud_bloodgrp);
// HttpPost mURL = new HttpPost("http://10.160.0.18:86/Service.svc/testpersondatapost?uid="+mStudentUserid+"&stdname="+stud_name+"&stdmail="+stud_email+"&Add="+stud_address+"&Qual=xyz&Qual_add=abc&pro_expert=abc&achieve=abc&Cont_no="+stud_mobileno+"&othr1=abc&othr2=abc&othr3=abc&proimgpath="+profileimagepath+"&UT=Student&Emer_ContPer="+stud_emrgperson+"&Emer_Cont_no="+stud_emrgcontact+"&Bld_Grp="+stud_bloodgrp+"&Addi_Notes"+;
String mURL = "http://webservice.zoomi.in/Service.svc/testpersondatapost?uid="+mStudentUserid+"&stdname="+stud_name+"&stdmail="+stud_email+"&Add="+stud_address+"&Qual=xyz&Qual_add=abc&pro_expert=abc&achieve=abc&Cont_no="+stud_mobileno+"&othr1=abc&othr2=abc&othr3=abc&proimgpath="+profileimagepath+"&UT=Student&Emer_ContPer="+stud_emrgperson+"&Emer_Cont_no="+stud_emrgcontact+"&Bld_Grp="+stud_bloodgrp+"&Addi_Notes=abc";
// String mURL = "http://webservice.zoomi.in/Service.svc/testpersondatapost?uid="+mStudentUserid+"&stdname="+stud_name+"&stdmail="+stud_email+"&Add="+stud_address+"&Qual=xyz&Qual_add=abc&pro_expert=abc&achieve=abc&Cont_no="+stud_mobileno+"&othr1=abc&othr2=abc&othr3=abc&proimgpath="+profileimagepath+"&UT=Student&Emer_ContPer="+stud_emrgperson+"&Emer_Cont_no="+stud_emrgcontact+"&Bld_Grp="+stud_bloodgrp+"";
// String mURL = "http://10.160.0.18:86/Service.svc/testpersondatapost?uid="+mStudentUserid+"&stdname="+stud_name+"&stdmail="+stud_email+"&Add="+stud_address+"&Qual=xyz&Qual_add=abc&pro_expert=abc&achieve=abc&Cont_no="+stud_mobileno+"&othr1=abc&othr2=abc&othr3=abc&proimgpath="+profileimagepath+"&UT=Student&Emer_ContPer="+stud_emrgperson+"&Emer_Cont_no="+stud_emrgcontact+"&Bld_Grp="+stud_bloodgrp+"";
HttpPost postrequest = new HttpPost(mURL);
MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
FileBody fileBody = new FileBody(new File(Environment.getExternalStorageDirectory()+"/data/.System/MProfile/", myImage[1]));//,"application/octet-stream");
reqEntity.addPart("fileContents", fileBody);
try {
postrequest.setEntity(reqEntity);
//Execute the request "POST"
httpResp = httpClient.execute(postrequest);
/*HttpResponse response = null;*/
//Check the status code, in this case "created"
//Log.v("App", "Created");
int code = httpResp.getStatusLine().getStatusCode();
System.out.println("Response Code : "+code);
/*if (((HttpResponse) response).getStatusLine().getStatusCode() == HttpStatus.SC_CREATED)
{
}*/
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
int responcecode = httpResp.getStatusLine().getStatusCode();
if(responcecode==200)
{
Intent stopserviceintnet = new Intent(mContext,MyServiceProf.class);
mContext.stopService(stopserviceintnet);
System.out.print("Your service is stopped...");
try{
MyclassFragment.mbtn_SaveMyProfile.setEnabled(true);
}
catch (Exception e) {
//TODO: handle exception
}
try{
QuickaccessFragment.mbtn_SaveMyProfile.setEnabled(true);
}
catch (Exception e) {
//TODO: handle exception
}
}else
{
System.out.print("Your service is running...");
}
System.out.println(jsonResponse);
return jsonResponse;
}

}

Parfois, Cela fonctionne correctement, mais tout à coup, mon apps a été Écrasé alors que le wifi ou la connexion Internet Mobile est connecté, je pense que le service ne fonctionnera pas correctement. 🙁
En attente de votre suggestion, de solutions et de vos idées.
Merci.