code: public Long del(H key) {
          final byte[] rawKey = rawKey(key);
  
          return execute(new RedisCallback<Long>() {
              public Long doInRedis(RedisConnection connection) throws DataAccessException {
                  return ((RedisClusterConnection) connection).ssDel(rawKey);
              }
          }, true);
      }
docs: /*
  @see SessionOfHashSetOperations#del(java.lang.Object)