@Override
  public String save() throws Exception {
    SystemContext context = this.getSystyemContext();

    // 设置最后更新人的信息
    Cert4RoadTransport e = this.getE();
    e.setModifier(context.getUserHistory());
    e.setModifiedDate(Calendar.getInstance());
    this.getCrudService().save(e);

    // 保存证件与车辆的关联表信息
    if (carId != null) {
      this.certService.carNCert4Save(carId, getE().getId());
    }

    return "saveSuccess";
  }