public void execute()

in gateway-server/src/main/java/org/apache/knox/gateway/util/KnoxCLI.java [2462:2523]
56 lines of code
14 McCabe index (conditional complexity)

    public void execute() throws Exception {
      if (StringUtils.isBlank(FilenameUtils.getExtension(providerName))
          || StringUtils.isBlank(FilenameUtils.getExtension(descriptorName))) {
        throw new IllegalArgumentException(
            " JSON extension is required for provider and descriptor file names");
      }

      final TopologyToDescriptor converter = new TopologyToDescriptor();

      converter.setForce(force);
      if (!StringUtils.isBlank(topologyName)) {
        converter.setTopologyPath(
            getGatewayConfig().getGatewayTopologyDir() + File.separator
                + topologyName);
      } else if (!StringUtils.isBlank(path)) {
        converter.setTopologyPath(path);
      } else {
        throw new IllegalArgumentException(
            "Please specify either --path or --topology-name option");
      }
      if (!StringUtils.isBlank(providerName)) {
        converter.setProviderName(providerName);
      }
      if (!StringUtils.isBlank(descriptorName)) {
        converter.setDescriptorName(descriptorName);
      }
      /* if output location is provided then use it */
      if (!StringUtils.isBlank(outputDir)) {
        converter.setProviderConfigDir(outputDir);
        converter.setDescriptorConfigDir(outputDir);
      } else {
        converter.setProviderConfigDir(
            getGatewayConfig().getGatewayProvidersConfigDir());
        converter.setDescriptorConfigDir(
            getGatewayConfig().getGatewayDescriptorsDir());
      }
      /* set discovery params */
      if (!StringUtils.isBlank(cluster)) {
        converter.setCluster(cluster);
      }
      if (!StringUtils.isBlank(discoveryUrl)) {
        converter.setDiscoveryUrl(discoveryUrl);
      }
      if (!StringUtils.isBlank(discoveryUser)) {
        converter.setDiscoveryUser(discoveryUser);
      }
      if (!StringUtils.isBlank(discoveryPasswordAlias)) {
        converter.setDiscoveryPasswordAlias(discoveryPasswordAlias);
      }
      if (!StringUtils.isBlank(discoveryType)) {
        converter.setDiscoveryType(discoveryType);
      }

      converter.validate();
      converter.convert();

      final String topoName = StringUtils.isBlank(topologyName) ?  FilenameUtils.getBaseName(path) : topologyName;
      out.println(
          "Provider " + providerName + " and descriptor " + descriptorName
              + " generated for topology " + topoName
              + "\n");
    }