Java在线问卷系统实现与统计解析

@Entity
public class Survey {
    @Id @GeneratedValue
    private Long id;
    private String title;
    @OneToMany(mappedBy = "survey", cascade = CascadeType.ALL)
    private List questions;
    // getter/setter
}

@Entity
public class Question {
    @Id @GeneratedValue
    private Long id;
    private String content;
    private String type; // "SINGLE", "MULTI", "TEXT"
    @OneToMany(mappedBy = "question", cascade = CascadeType.ALL)
    private List options;
    @ManyToOne
    private Survey survey;
}

@Entity
public class Response {
    @Id @GeneratedValue
    private Long id;
    private String respondentIp;
    private LocalDateTime submitTime;
    @ManyToOne
    private Survey survey;
}

@Entity
public class Answer {
    @Id @GeneratedValue
    private Long id;
    @ManyToOne
    private Response response;
    @ManyToOne
    private Option option; // 可为空，文本题用answerText
    private String answerText;
}

@Service
public class StatisticService {
    
    @Autowired
    private AnswerRepository answerRepo;

    public Map countOptionsByQuestion(Long questionId) {
        List results = answerRepo.countByOptionInQuestion(questionId);
        Map stat = new HashMap<>();
        for (Object[] row : results) {
            String optionContent = (String) row[0];
            Long count = (Long) row[1];
            stat.put(optionContent, count.intValue());
        }
        return stat;
    }
}

@Query("SELECT o.content, COUNT(a) FROM Answer a " +
       "JOIN a.option o JOIN o.question q " +
       "WHERE q.id = :qid GROUP BY o.content")
List countByOptionInQuestion(@Param("qid") Long qid);