如何清除BufferedReader如果它不是空的[Java/Android]

我不明白如何清除BufferedReader。當我在Activity中按下按鈕時，變量設置爲1或2.取決於BufferedReader中的數字更改文件。當我在緩衝區第二次推入將是兩個文件。如何在上傳之前告訴BR清除緩衝區。反之亦然，當然。如何清除BufferedReader如果它不是空的[Java/Android]

public List<String> getQuestionLinesList() { 

      String line; 
      List<String> lines = new ArrayList<String>(); 
      Log.d(TAG, " Trying to get resourses"); 
      Resources res = context.getResources(); 


      try { 

        if (selectedBox == 1) { 

         bufferedQuestions = new BufferedReader(new InputStreamReader(res.openRawResource(R.raw.questions_list))); 

        } else if (selectedBox == 2) { 

         bufferedQuestions = new BufferedReader(new InputStreamReader(res.openRawResource(R.raw.questions_list_art))); 

        } 


       Log.d(TAG, "number i = " + Integer.toString(selectedBox)); 

       while ((line = bufferedQuestions.readLine()) != null) { 
        lines.add(line); 
        Log.d(LINETAG, line); 
       } 

      } catch (IOException e) { 
       e.printStackTrace(); 
      } 

      return lines; 
     }

來源

2015-09-07 bronnikov