public TShowTopicResp showTopic(TShowTopicReq req) {
    try {
      return ((TopicTableResp) configManager.getConsensusManager().read(new ShowTopicPlan()))
          .filter(req.topicName, req.isTableModel)
          .convertToTShowTopicResp();
    } catch (Exception e) {
      LOGGER.warn("Failed to show topic info.", e);
      return new TopicTableResp(
              new TSStatus(TSStatusCode.SHOW_TOPIC_ERROR.getStatusCode())
                  .setMessage(e.getMessage()),
              Collections.emptyList())
          .convertToTShowTopicResp();
    }
  }
Caller should ensure that the method is called in the write lock of {@link #subscriptionInfo}.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/subscription/SubscriptionCoordinator.java