Jedis运用scan删除正则匹配的key

我们都知道用keys *进行查询key的时候会进行堵塞,导致redis整体不可用,而使用scan命令则不会.

RedisServiceImpl中scan的内容为

@Override
public ScanResult scan(String cursor, ScanParams params) {
    return execute(new RedisFunction<ScanResult, Jedis>() {

        @Override
        public ScanResult callback(Jedis jedis) {
            return jedis.scan(cursor,params);
        }

    });
}

然后定义一个工具类

public class RedisUntil {
    public static List<String> getScan(RedisService redisService,String key) {
        List<String> list = new ArrayList<>();
        ScanParams params = new ScanParams();
        params.match(key);
        params.count(100);
        String cursor = "0";
        while (true) {
            ScanResult scanResult = redisService.scan(cursor,params);
            List<String> elements = scanResult.getResult();
            if (elements != null && elements.size() > 0) {
                list.addAll(elements);
            }
            cursor = scanResult.getStringCursor();
            if ("0".equals(cursor)) {
                break;
            }
        }
        return list;
    }
}

使用该工具类进行批量删除,假设我们要删除的是以"userpage:"为前缀

List<String> keyList = RedisUntil.getScan(redisService,"userpage:*");
for (String key:keyList) {
    redisService.del(key);
}

这样在生产环境中就不会堵塞redis.