code: public List<CandidateAnswer> getAllCandidateAnswer() {
          Map<String, Double> map = new HashMap<>();
          for (Evidence evidence : evidences) {
              for (CandidateAnswer candidateAnswer : evidence.getCandidateAnswerCollection().getAllCandidateAnswer()) {
                  Double score = map.get(candidateAnswer.getAnswer());
                  //候选答案的分值和证据的分值 用于计算最终的候选答案分值
                  Double candidateAnswerFinalScore = candidateAnswer.getScore() + evidence.getScore();
                  if (score == null) {
                      score = candidateAnswerFinalScore;
                  } else {
                      score += candidateAnswerFinalScore;
                  }
                  map.put(candidateAnswer.getAnswer(), score);
              }
          }
  
          //组装候选答案
          List<CandidateAnswer> candidateAnswers = new ArrayList<>();
          for (Map.Entry<String, Double> entry : map.entrySet()) {
              String answer = entry.getKey();
              Double score = entry.getValue();
              if (answer != null && score != null && score > 0 && score < Double.MAX_VALUE) {
                  CandidateAnswer candidateAnswer = new CandidateAnswer();
                  candidateAnswer.setAnswer(answer);
                  candidateAnswer.setScore(score);
                  candidateAnswers.add(candidateAnswer);
              }
          }
          Collections.sort(candidateAnswers);
          Collections.reverse(candidateAnswers);
          //过滤候选答案
          if (candidateAnswerFilter != null) {
              candidateAnswerFilter.filter(this, candidateAnswers);
          }
          //分值归一化
          if (candidateAnswers.size() > 0) {
              double baseScore = candidateAnswers.get(0).getScore();
              for (CandidateAnswer candidateAnswer : candidateAnswers) {
                  double score = candidateAnswer.getScore() / baseScore;
                  candidateAnswer.setScore(score);
              }
          }
  
          return candidateAnswers;
      }
docs: 获取所有候选答案
  
  @return 所有候选答案