RedisTemplate批量获取Key

    private static final Integer SCAN_COUNT = 10000;
    /**
     * 使用scan遍历key
     * 为什么不使用keys 因为Keys会引发Redis锁，并且增加Redis的CPU占用,特别是数据庞大的情况下。这个命令千万别在生产环境乱用。
     * 支持redis单节点和集群调用
     *
     * @param matchKey
     * @return
     */
    public Set<String> scanMatch(String matchKey) {
        Set<String> keys = new HashSet();
        RedisConnectionFactory connectionFactory = redisTemplate.getConnectionFactory();
        RedisConnection redisConnection = connectionFactory.getConnection();
        Cursor<byte[]> scan = null;
        //集群
        if(redisConnection instanceof JedisClusterConnection){
            RedisClusterConnection clusterConnection = connectionFactory.getClusterConnection();
            Iterable<RedisClusterNode> redisClusterNodes = clusterConnection.clusterGetNodes();
            Iterator<RedisClusterNode> iterator = redisClusterNodes.iterator();
            while (iterator.hasNext()) {
                RedisClusterNode next = iterator.next();
                scan = clusterConnection.scan(next, ScanOptions.scanOptions().match(matchKey).count(Integer.MAX_VALUE).build());
                while (scan.hasNext()) {
                    keys.add(new String(scan.next()));
                }
                try {
                    if(scan !=null){
                        scan.close();
                    }
                } catch (IOException e) {
                    log.error("scan遍历key关闭游标异常",e);
                }
            }
            return keys;
        }
        //单机
        if(redisConnection instanceof JedisConnection){
        scan = redisConnection.scan(ScanOptions.scanOptions().match(matchKey + "*").count(SCAN_COUNT).build());
        while (scan.hasNext()) {
            //找到一次就添加一次
            keys.add(new String(scan.next()));
        }
        try {
            if (scan != null) {
                scan.close();
            }
        } catch (IOException e) {
            log.error("scan遍历key关闭游标异常", e);
        }
        return keys;
        }

        return keys;

    }

SCAN cursor [MATCH pattern] [COUNT count]

SCAN 0 MATCH user_* COUNT 10000