output: #fixed code
                                  @Override
      public final boolean incrementToken() throws IOException {
          String token = getToken();
          if (token != null) {
              charTermAttribute.setEmpty().append(token);
              return true;
          }
          return false;
      }
input: #vulnerable code 
                                  @Override
      public final boolean incrementToken() throws IOException {
          Word word = getWord();
          if (word != null) {
              int positionIncrement = 1;
              //忽略停用词
              while(StopWord.is(word.getText())){
                  positionIncrement++;
                  startOffset += word.getText().length();
                  LOGGER.debug("忽略停用词："+word.getText());
                  word = getWord();
                  if(word == null){
                      return false;
                  }
              }
              charTermAttribute.setEmpty().append(word.getText());
              offsetAttribute.setOffset(startOffset, startOffset+word.getText().length());
              positionIncrementAttribute.setPositionIncrement(positionIncrement);
              startOffset += word.getText().length();
              //词性标注
              if(POS){
                  PartOfSpeechTagging.process(Arrays.asList(word));
                  partOfSpeechAttribute.setEmpty().append(word.getPartOfSpeech().getPos());
              }
              //拼音标注
              if(PINYIN){
                  PinyinTagging.process(Arrays.asList(word));
                  acronymPinyinAttribute.setEmpty().append(word.getAcronymPinYin());
                  fullPinyinAttribute.setEmpty().append(word.getFullPinYin());
              }
              //同义标注
              if(SYNONYM){
                  SynonymTagging.process(Arrays.asList(word));
                  StringBuilder synonym = new StringBuilder();
                  word.getSynonym().forEach(w -> synonym.append(w.getText()).append(" "));
                  synonymAttribute.setEmpty().append(synonym.toString().trim());
              }
              //反义标注
              if(ANTONYM){
                  AntonymTagging.process(Arrays.asList(word));
                  StringBuilder antonym = new StringBuilder();
                  word.getAntonym().forEach(w -> antonym.append(w.getText()).append(" "));
                  antonymAttribute.setEmpty().append(antonym.toString().trim());
              }
              return true;
          }
          return false;
      } 
                              #location 17 
                              #vulnerability type NULL_DEREFERENCE