api/java/src/main/java/com/navercorp/redis/cluster/spring/AbstractOperations.java
byte[][] rawKeys(K key, Collection<K> keys) {
        final byte[][] rawKeys = new byte[keys.size() + (key != null ? 1 : 0)][];

        int i = 0;

        if (key != null) {
            rawKeys[i++] = rawKey(key);
        }

        for (K k : keys) {
            rawKeys[i++] = rawKey(k);
        }

        return rawKeys;
    }
byte[][] rawKeys(K key, Collection<K> keys) {
        final byte[][] rawKeys = new byte[keys.size() + (key != null ? 1 : 0)][];

        int i = 0;

        if (key != null) {
            rawKeys[i++] = rawKey(key);
        }

        for (K k : keys) {
            rawKeys[i++] = rawKey(k);
        }

        return rawKeys;
    }
Raw keys.

@param key  the key
@param keys the keys
@return the byte[][]