code: @Override
    public void close() throws Exception {
  
      if (this.lookupClient != null) {
        this.lookupClient.close();
      }
  
      if (this.registryClient != null) {
        this.registryClient.close();
      }
  
      if (this.transport != null) {
        this.transport.close();
      }
    }
docs: Closes resources.