code: static Startup defaultStartup(MessageHandler mh) {
          if (defaultStartup != null) {
              return defaultStartup;
          }
          try {
              String content = readResource(DEFAULT_STARTUP_NAME);
              return defaultStartup = new Startup(
                      new StartupEntry(true, DEFAULT_STARTUP_NAME, content));
          } catch (AccessDeniedException e) {
              mh.errormsg("jshell.err.file.not.accessible", "jshell", DEFAULT_STARTUP_NAME, e.getMessage());
          } catch (NoSuchFileException e) {
              mh.errormsg("jshell.err.file.not.found", "jshell", DEFAULT_STARTUP_NAME);
          } catch (Exception e) {
              mh.errormsg("jshell.err.file.exception", "jshell", DEFAULT_STARTUP_NAME, e);
          }
          return defaultStartup = noStartup();
      }
docs: Factory method: The default Startup ("-default.").
  
  @param mh handler for error messages
  @return The default Startup, or empty startup when error (message has been printed)