docs: public static void main(String[] args) {
          Twitter twitter = new TwitterFactory().getInstance();
          try {
              String cursor = null;
              int count = 20;
              DirectMessageList messages;
              do {
                  System.out.println("* cursor:" + cursor);
                  messages = cursor == null ? twitter.getDirectMessages(count) : twitter.getDirectMessages(count, cursor);
                  for (DirectMessage message : messages) {
                      System.out.println("From: " + message.getSenderId() + " id:" + message.getId()
                              + " [" + message.getCreatedAt() + "]"
                              + " - " + message.getText());
                      System.out.println("raw[" + message + "]");
                  }
                  cursor = messages.getNextCursor();
              } while (messages.size() > 0 && cursor != null);
              System.out.println("done.");
              System.exit(0);
          } catch (TwitterException te) {
              te.printStackTrace();
              System.out.println("Failed to get messages: " + te.getMessage());
              System.exit(-1);
          }
      }