code: public static void main(String[] args) throws Exception {
          try {
              new Subscriber(args).run();
          } catch (IllegalArgumentException e) {
              System.out.flush();
              System.err.println(e.getMessage());
              Subscriber.usage();
              System.err.flush();
              throw e;
          }
      }
docs: Subscribes to a subject.
  
  @param args the subject, cluster info, and subscription options