docs: public static void main(String[] args) {
          if (args.length < 1) {
              System.out.println("Usage: java twitter4j.examples.directmessage.ShowDirectMessage [message id]");
              System.exit(-1);
          }
          Twitter twitter = new TwitterFactory().getInstance();
          try {
              DirectMessage message = twitter.showDirectMessage(Long.parseLong(args[0]));
              System.out.println("From: id:" + message.getId() + " - "
                      + message.getText());
              System.exit(0);
          } catch (TwitterException te) {
              te.printStackTrace();
              System.out.println("Failed to get message: " + te.getMessage());
              System.exit(-1);
          }
      }