android 使用SQLiteOpenHelper类批量执行sql问题

try {        InputStream in = mContext.getAssets().open("update_cities.sql");        SQLiteDatabase database = getWritableDatabase();        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(in));        String sqlUpdate = null;         while ((sqlUpdate = bufferedReader.readLine()) != null) {                    if (!TextUtils.isEmpty(sqlUpdate)) {                            database.execSQL(sqlUpdate);                                                }                                        }                         bufferedReader.close();                         in.close();         } catch (SQLException e) {                     XLog.log(TAG, e.getMessage());          } catch (IOException e) {                     XLog.log(TAG, e.getMessage());                                } 

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