code: public boolean check(Long pipelineId) {
          MainstemMonitor mainstemMonitor = ArbitrateFactory.getInstance(pipelineId, MainstemMonitor.class);
          return mainstemMonitor.check();
      }
docs: 检查下当前的mainstem是否可以运行(在await获取成功后，每次执行业务之前进行check)