Java Code Examples for redis.clients.jedis.Jedis#scan()

public List<String> scanKeys(String key) {
    Jedis jedis = null;
    try {
        jedis = jedisPool.getResource();
        List<String> keys = new ArrayList<String>();
        String cursor = "0";
        ScanParams sp = new ScanParams();
        sp.match("*" + key + "*");
        sp.count(100);
        do {
            ScanResult<String> ret = jedis.scan(cursor, sp);
            List<String> result = ret.getResult();
            if (result != null && result.size() > 0) {
                keys.addAll(result);
            }
            //再处理cursor
            cursor = ret.getStringCursor();
        } while (!cursor.equals("0"));
        return keys;
    } finally {
        if (jedis != null) {
            jedis.close();
        }
    }
}
 

@Override
public ScanResult<String> scan(final long cursor, final ScanParams params) {
    ShardedJedis shardedJedis = null;
    try {
        shardedJedis = POOL.getJedis(config.getRedisType());
        final Collection<Jedis> allJedis = shardedJedis.getAllShards();
        if (allJedis.size() == 1) {
            final Jedis jedis = allJedis.iterator().next();
            if (params == null) {
                return jedis.scan(String.valueOf(cursor), DEFAULT_SCAN_PARAMS);
            } else {
                return jedis.scan(String.valueOf(cursor), params);
            }
        } else {
            throw new RedisClientException("不支持对多节点Sharded模式进行Scan操作");
        }
    } catch (final Throwable e) {
        if (e instanceof RedisClientException) {
            throw e;
        }

        throw new RedisClientException(e.getMessage(), e);
    } finally {
        POOL.close(shardedJedis);
    }
}
 

/**
 * Performs the actual scan command using the native client implementation.
 * The given {@literal options} are never {@code null}.
 * 
 * @param jedis
 * @return
 */
protected synchronized ScanIterable<byte[]> doScanNode(Jedis jedis) {
	ScanResult<byte[]> res = jedis.scan(getCursor().getCursorByteArray(), params);

	List<byte[]> items = res.getResult();
	if (isEmpty(items)) {
		items = emptyList();
	}

	return new ScanIterable<byte[]>(cursor.setCursor(res.getStringCursor()), items);
}
 

private static void deleteExistingKeys(Jedis node) throws Exception {
  String nextCursor = "0";
  Set<String> matchingKeys = new HashSet<>();
  ScanParams params = new ScanParams();
  params.match("*");

  // get all of the keys for the particular node
  do {
    ScanResult scanResult = node.scan(nextCursor, params);
    List<String> keys = scanResult.getResult();
    nextCursor = scanResult.getCursor();

    matchingKeys.addAll(keys);

  } while (!nextCursor.equals("0"));

  if (matchingKeys.size() == 0) {
    return;
  }

  // we cannot pass all of the keys to del because of the following error:
  // "CROSSSLOT Keys in request don't hash to the same slot"
  // so iterate over and delete them individually.
  for (String key : matchingKeys.toArray(new String[matchingKeys.size()])) {
    node.del(key);
  }
}
 

private ScanResult<String> scan_match_count(Jedis j, String cursor, String pattern, int count) {
	ScanParams param = new ScanParams();
	param.match(pattern);
	param.count(count);
	redis.clients.jedis.ScanResult<String> sr = j.scan(cursor, param);
	return new ScanResult<String>(sr.getStringCursor(), sr.getResult());
}
 

private ScanResult<String> scan0(Jedis j, String cursor) {
	redis.clients.jedis.ScanResult<String> sr = j.scan(cursor);
	return new ScanResult<String>(sr.getStringCursor(), sr.getResult());
}
 

private ScanResult<String> scan_count(Jedis j, String cursor, int count) {
	ScanParams param = new ScanParams();
	param.count(count);
	redis.clients.jedis.ScanResult<String> sr = j.scan(cursor, param);
	return new ScanResult<String>(sr.getStringCursor(), sr.getResult());
}
 

private ScanResult<String> scan_match(Jedis j, String cursor, String pattern) {
	ScanParams param = new ScanParams();
	param.match(pattern);
	redis.clients.jedis.ScanResult<String> sr = j.scan(cursor, param);
	return new ScanResult<String>(sr.getStringCursor(), sr.getResult());
}
 

public ScanResult<String> scan(Jedis jedis, String cursor, ScanParams scanParams) {
    return jedis.scan(cursor, scanParams);
}