SQLiteOpenHelper getWritableDatabse() fails with no Exception
- by Michal K
I have a very strange problem. It only shows from time to time, on several devices. Can't seem to reproduce it when I want, but had it so many times, that I think I know where I get it.
So I have a Loader which connects to sqlite through a singleton SQLiteOpenHelper:
try{
Log.i(TAG, "Get details offline / db helper: "+DatabaseHelper.getInstance(getContext()));
SQLiteDatabase db=DatabaseHelper.getInstance(this.getContext()).getWritableDatabase();
Log.i(TAG, "Get details offline / db: "+db);
//doing some work on the db
//...
} catch(SQLiteException e){
e.printStackTrace();
return null;
} catch(Exception e){
e.printStackTrace();
return null;
//trying everything to grab some exception or whatever
}
My SQLIteOpenHelper looks something like this:
public class DatabaseHelper extends SQLiteOpenHelper {
private static DatabaseHelper mInstance = null;
private static Context mCxt;
public static DatabaseHelper getInstance(Context cxt) {
//using app context ass suggested by CommonsWare
Log.i("DBHELPER1", "cxt"+mCxt+" / instance: "+mInstance);
if (mInstance == null) {
mInstance = new DatabaseHelper(cxt.getApplicationContext());
}
Log.i("DBHELPER2", "cxt"+mCxt+" / instance: "+mInstance);
mCxt = cxt;
return mInstance;
}
//private constructor
private DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.mCxt = context;
}
@Override
public void onCreate(SQLiteDatabase db) {
//some tables created here
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//upgrade code here
}
It really works great in most cases. But from time to time I get a log similar to this:
06-10 23:49:59.621: I/DBHELPER1(26499): cxtcom.bananout.Bananout@407152c8 / instance: com.bananout.helpers.DatabaseHelper@40827560
06-10 23:49:59.631: I/DBHELPER2(26499): cxtcom.bananout.Bananout@407152c8 / instance: com.bananout.helpers.DatabaseHelper@40827560
06-10 23:49:59.631: I/DetailsLoader(26499): Get event details offline / db helper: com.bananout.helpers.DatabaseHelper@40827560
06-10 23:49:59.631: I/DBHELPER1(26499): cxtcom.bananout.Bananout@407152c8 / instance: com.bananout.helpers.DatabaseHelper@40827560
06-10 23:49:59.651: I/DBHELPER2(26499): cxtcom.bananout.Bananout@407152c8 / instance: com.bananout.helpers.DatabaseHelper@40827560
This line Log.i(TAG, "Get details offline / db: "+db); never gets called! No Exceptions, silence. Plus, the thread with the Loader is not running anymore.
So nothing past this line SQLiteDatabase db=DatabaseHelper.getInstance(this.getContext()).getWritableDatabase(); gets executed.
What can possibly go wrong on this line?