code: void doGroupStart(String group, String name, Object args, String parent) {
      checkOpen();
      JsonObject message = createMessage(args)
          .putString("group", group)
          .putString("name", name)
          .putString("parent", parent)
          .putString("action", "startGroup");
      if (open && !paused) {
        if (log.isDebugEnabled()) {
          if (parent != null) {
            log.debug(String.format("%s - Group start: Group[name=%s, group=%s, parent=%s, args=%s]", this, name, group, parent, args));
          } else {
            log.debug(String.format("%s - Group start: Group[name=%s, group=%s, args=%s]", this, name, group, args));
          }
        }
        eventBus.send(inAddress, message);
      }
      checkFull();
    }
docs: Sends a group start message.