redis - 无法使用 redis 模板扫描

Question

我正在尝试使用 SCAN http://redis.io/commands/scan来遍历 redis 中存在的所有键。但是spring提供的Redis模板没有scan()方法。使用上述方法有什么技巧吗？

谢谢

Answer 1

您可以使用RedisCallbackonRedisOperations来执行此操作。

redisTemplate.execute(new RedisCallback<Iterable<byte[]>>() {

  @Override
  public Iterable<byte[]> doInRedis(RedisConnection connection) throws DataAccessException {

    List<byte[]> binaryKeys = new ArrayList<byte[]>();

    Cursor<byte[]> cursor = connection.scan(ScanOptions.NONE);
    while (cursor.hasNext()) {
      binaryKeys.add(cursor.next());
    }

    try {
      cursor.close();
    } catch (IOException e) {
      // do something meaningful
    }

    return binaryKeys;
  }
});

Answer 2

Set<String> keys = (Set<String>) redisTemplate.execute((RedisCallback<Set<String>>) connection -> {
            Cursor<byte[]> cursor = null;
            Set<String> keysTmp = new HashSet<>();
            try {
                cursor = connection.scan(new ScanOptions.ScanOptionsBuilder().match(keyPrefix + "*").count(10000).build());
                while (cursor.hasNext()) {
                    keysTmp.add(new String(cursor.next()));
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (Objects.nonNull(cursor) && !cursor.isClosed()) {
                    try {
                        cursor.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
            return keysTmp;
        });