vote_java/src/main/java/com/lh/service/VoteConsumer.java

package com.lh.service;

import com.lh.bean.Candidate;
import com.lh.exception.MyException;
import com.lh.mapper.CandidatesMapper;
import com.lh.mapper.VoterMapper;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.kafka.annotation.EnableKafka;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;

@Service
@EnableKafka
public class VoteConsumer {
    @Autowired
    private VoterMapper voterMapper;
    @Autowired
    private CandidatesMapper candidatesMapper;
    @Autowired
    private StringRedisTemplate redisTemplate;

    @KafkaListener(topics = "vote-topic", groupId = "vote-group")
    public void handleVoteMessage(ConsumerRecord<String, String> record) throws MyException {
        String message = record.value();

        // 将消息分割为投票信息
        String[] parts = message.split(",");
        String voterJwcode = parts[0];
        String candidateJwcode = parts[1];
        String voterName = parts[2];
        String voteTime = parts[3];

        // 处理投票
        processVote(voterJwcode, candidateJwcode, voterName, voteTime);
    }

    private boolean processVote(String voterJwcode, String candidateJwcode, String voterName, String voteTime) throws MyException {
        // 获取候选人信息
        Candidate candidate = candidatesMapper.getByCandidateJwcode(candidateJwcode);

        // 2. 获取候选人信息
        if (candidate == null) {
            throw new MyException("候选人不存在！");
        }

        // 3. 检查用户是否已经为该候选人投过票
        //List<Voter> hasVotes = voterMapper.countVotesToday(voterJwcode);
        ////遍历列表，判断是否有记录
        //boolean flag = true;
        //for (Voter vote : hasVotes) {
        //    if (vote.getCandidateJwCode().equals(candidateJwcode)) {
        //        flag = false;
        //    }
        //}
        //if (!flag){
        //    throw new MyException("已投票，可以选择其他人试试哦~");
        //}

        // 4. 增加候选人票数
        if (!candidatesMapper.addVotes(candidateJwcode)) {
            throw new MyException ("候选人票数更新失败，请联系管理员！");
        }

        // 5. 插入投票记录
        voterMapper.insertVote(voterJwcode, candidateJwcode, voterName);


        System.out.println("投票成功！用户：" + voterJwcode + " 投给了 " + candidateJwcode);
        return true;
    }

}