code: private byte[][] toByteArrays(final byte[] keyspace, final byte[] uid, final byte[] serviceCode, final byte[][] key) {
          final byte[][] allArgs = new byte[key.length + 3][];
          int index = 0;
          allArgs[index++] = keyspace;
          allArgs[index++] = uid;
          allArgs[index++] = serviceCode;
  
          for (int i = 0; i < key.length; i++) {
              allArgs[index++] = key[i];
          }
          return allArgs;
      }
docs: To byte arrays.
  
  @param keyspace    the keyspace
  @param uid         the uid
  @param serviceCode the service code
  @param key         the key
  @return the byte[][]