Retrieve data from a SQLiite database

i have problem to retrieve data from database using this method getData()

DataBase Class

public void getData(int id) {
   SQLiteDatabase db = this.getReadableDatabase();

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

   if (c != null)
       c.moveToFirst();

   // ArrayList<String> array =new ArrayList<String>();
   Locationxy locationxy = new Locationxy();
   locationxy.setId(c.getString(0));
   locationxy.setLan(c.getString(1));
   locationxy.setLon(c.getString(2));

   Log.i(c.getString(1), c.getString(2));

   array.add(c.getString(0));
    array.add(c.getString(1));
    array.add(c.getString(2));

}

MapClass

or(int i=0 ;i<=5 ;i++) {
     if(db!=null) {

         db.getData(i);

         locationB.setLatitude(Double.parseDouble(locationxy.getLan()));
         locationB.setLongitude(Double.parseDouble(locationxy.getLon()));}}

getData() method makes error , and leave application