<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>28.0-jre</version>
</dependency>

import com.google.common.hash.BloomFilter;
import com.google.common.hash.Funnels;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.nio.charset.Charset;
@Configuration
public class BloomFilterConfig {
    /**
     * expectedInsertions：期望添加的數(shù)據(jù)個(gè)數(shù)
     * fpp：期望的誤判率，期望的誤判率越低，布隆過濾器計(jì)算時(shí)間越長(zhǎng)
     * @return
     */
    @Bean
    public BloomFilter<String> goodsIDBloom(){
        BloomFilter<String> filter = BloomFilter.create(Funnels.stringFunnel(Charset.forName("utf-8")), 1000,0.00001);
        return filter;
    }
    @Bean
    public BloomFilter<String> orderBloom(){
        BloomFilter<String> filter = BloomFilter.create(Funnels.stringFunnel(Charset.forName("utf-8")), 1000,0.00001);
        return filter;
    }
}

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.google.common.hash.BloomFilter;
import com.liu.seckill.entity.SeckillGood;
import com.liu.seckill.service.SeckillGoodService;
import com.liu.seckill.service.UserService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.scheduling.annotation.Scheduled;
import java.time.Duration;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;
 
@Slf4j
@Configuration
public class InitConfig implements InitializingBean {
    @Autowired
    UserService userService;
    @Autowired
    SeckillGoodService seckillGoodService;
    @Autowired
    RedisTemplate redisTemplate;
    @Autowired
    RedisConfig redisConfig;
    @Autowired
    @Qualifier("goodsIDBloom")
    BloomFilter<String> goodsIDBloom;
    /**
     * 把商品庫(kù)存加載到 Redis中
     * 每天更新
     * @throws Exception
     */
    @Override
    @Scheduled(fixedRate = 1000*60*60*24)
    public void afterPropertiesSet() throws Exception {
        //只緩存秒殺還沒結(jié)束或秒殺還沒開始的商品
        List<SeckillGood> seckillGoods = seckillGoodService.list(new QueryWrapper<SeckillGood>().ge("end_time", LocalDateTime.now()));
        if (seckillGoods == null) {
            log.info("暫無秒殺商品");
            return;
        }
        //將秒殺商品ID和庫(kù)存分別存入redis中
        List<Long> seckillGoodIDList = new ArrayList<>();
        for (SeckillGood seckillGood : seckillGoods) {
            seckillGoodIDList.add(seckillGood.getSgId());
            //設(shè)置過期時(shí)間
            long millis = Duration.between(LocalDateTime.now(), seckillGood.getEndTime()).toMillis();
            redisTemplate.opsForValue().set("seckillGoodID:" + seckillGood.getSgId(), seckillGood.getSgStock(), millis, TimeUnit.MILLISECONDS);
            //存儲(chǔ)值到布隆過濾器中
            goodsIDBloom.put(seckillGood.getSgId()+"");
        }
        redisTemplate.opsForValue().set("seckillGoodIDList:", seckillGoodIDList,1,TimeUnit.DAYS);
 
    }
}

@RestController
@RequestMapping("/seckillOrder")
public class SeckillOrderController  {
 	//如果有多個(gè)布隆過濾器，就同時(shí)使用@Qualifier和@Autowired
    @Autowired
    @Qualifier("goodsIDBloom")
    BloomFilter<String> goodsIDBloom;
    @Autowired
    @Qualifier("orderBloom")
    BloomFilter<String> orderBloom;
 
    @GetMapping("/seckillGoods/{goodId}")
    public Result seckillGoods(@PathVariable("goodId") Long goodId) {
        ValueOperations valueOperations = redisTemplate.opsForValue();
 
        //判斷秒殺商品是否存在
        //如果商品id在布隆過濾器中存在，那么就要再去判斷在不在redis中，在，才能證明真的在
        if (goodsIDBloom.mightContain(goodId+"")){
            ArrayList<Long> seckillGoodIDList = (ArrayList<Long>) valueOperations.get("seckillGoodIDList:");
            Assert.isTrue(seckillGoodIDList.contains(goodId),"未找到該商品，商品ID有誤或此商品不參與秒殺或此商品秒殺已結(jié)束");
        }else {
            Assert.isTrue(false,"未找到該商品，商品ID有誤或此商品不參與秒殺或此商品秒殺已結(jié)束");
        }
    }
}