code: public void sync() {
          if (this.client == null) {
              return;
          }
  
          List<Object> unformatted = null;
          try {
              unformatted = this.client.getAll();
          } catch (Exception e) {
              this.brokenResource = true;
              throw new GatewayException("gateway=" + this.server + ", connect=" + this.redis.connectInfo(), e);
          }
  
          if (unformatted == null) {
              return;
          }
  
          for (Object o : unformatted) {
              try {
                  generateResponse(o);
              } catch (Exception ignored) {
              }
          }
      }
docs: Synchronize pipeline by reading all responses. This operation close the
  pipeline. In order to get return values from pipelined commands, capture
  the different Response&lt;?&gt; of the commands you execute.