android.database.CursorIndexOutOfBoundsException: Index -1 requested, with a size of 0

android.database.CursorIndexOutOfBoundsException: Index -1 requested, with a size of 0

while placing debugger in the the method it is not going after the line

   double lans = c.getDouble(c.getColumnIndex(LAN));
     double  lons = c.getDouble(c.getColumnIndex(LON));

Can any one help me to solve it

public Locationxy getData(int id , DataBaseHelper dbHelper ) {
   SQLiteDatabase dbo = dbHelper.getReadableDatabase();
   Locationxy locationxy=new Locationxy();


   String[] coulmns = new String[]{BumpID, LAN, LON};
   String[] args = new String[]{String.valueOf(id)};
   Cursor c = dbo.query(TABLE_BUMPS, coulmns, BumpID + "=?",args, null, null, null, null);

   if ((c !=null ) && c.getCount()>0 )
       c.moveToFirst();
      double lans = c.getDouble(c.getColumnIndex(LAN));
     double  lons = c.getDouble(c.getColumnIndex(LON));

       locationxy = new Locationxy(lans, lons);





    return locationxy ;

} }