单点:

	public Set<String> scan(String matchKey) {
		Set<String> keys = (Set<String>) redisTemplate.execute((RedisCallback<Set<String>>) connection -> {
			Set<String> keysTmp = new HashSet<>();
			Cursor<byte[]> cursor = connection.scan(new ScanOptions.ScanOptionsBuilder().match(matchKey).count(1000).build());
			while (cursor.hasNext()) {
				keysTmp.add(new String(cursor.next()));
			}
			return keysTmp;
		});

		return keys;
	}

测试:

    @Test
    public void scan() {
        Set<String> stringSet = redisService.scan("*es*");
        System.out.println("*******************************************");
        System.out.println(stringSet);
        System.out.println("*******************************************");
    }

原文很详细:Spring RedisTemplate实现scan操作,毕竟keys不安全

集群:

public List<String> getRedisKeys(String matchKey) {

		List<String> list = new ArrayList<>();
		RedisClusterConnection redisClusterConnection = redisTemplate.getConnectionFactory().getClusterConnection();
		//这里是获取edispool的另外一种方式与上边的pipline可以对比下,两种方式都可以实现
		Map<String, JedisPool> clusterNodes = ((JedisCluster) redisClusterConnection.getNativeConnection()).getClusterNodes();
		for (Map.Entry<String, JedisPool> entry : clusterNodes.entrySet()) {
			//获取单个的jedis对象
			Jedis jedis = entry.getValue().getResource();
			// 判断非从节点(因为若主从复制,从节点会跟随主节点的变化而变化),此处要使用主节点从主节点获取数据
			if (!jedis.info("replication").contains("role:slave")) {
				List<String> keys = getScan(jedis, matchKey);
				if (keys.size() > 0) {
					Map<Integer, List<String>> map = new HashMap<>(8);
					//接下来的循环不是多余的,需要注意
					for (String key : keys) {
						// cluster模式执行多key操作的时候,这些key必须在同一个slot上,不然会报:JedisDataException:
						int slot = JedisClusterCRC16.getSlot(key);
						// 按slot将key分组,相同slot的key一起提交
						if (map.containsKey(slot)) {
							map.get(slot).add(key);
						} else {
							List<String> list1 = new ArrayList();
							list1.add(key);
							map.put(slot, list1);
						}
					}
					for (Map.Entry<Integer, List<String>> integerListEntry : map.entrySet()) {
						list.addAll(integerListEntry.getValue());
					}
				}
			}
		}
		return list;
	}

	public List<String> getScan(Jedis redisService, String key) {

		List<String> list = new ArrayList<>();
		//扫描的参数对象创建与封装
		ScanParams params = new ScanParams();
		params.match(key);
		//扫描返回一百行,这里可以根据业务需求进行修改
		params.count(100);
		String cursor = "0";
		ScanResult scanResult = redisService.scan(cursor, params);

		//scan.getStringCursor() 存在 且不是 0 的时候,一直移动游标获取
		while (null != scanResult.getStringCursor()) {
			//封装扫描的结果
			list.addAll(scanResult.getResult());
			if (! "0".equals( scanResult.getStringCursor())) {
				scanResult = redisService.scan(cursor, params);
			} else {
				break;
			}
		}
		return list;
	}

测试:

    @Test
    public void getRedisKeys() {

        List<String> list = redisService.getRedisKeys("*es*");
        System.out.println("*******************************************");
        System.out.println(list);
        System.out.println("*******************************************");
    }

原文很详细:关于在Redis集群模式下不支持Scan和pipline的解释以及解决方案

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