ModelAndView model = new ModelAndView();
model.setViewName("userAdd");
return model;
=========================================================================
返回数据
HashMap<String, Object> hashMap = new HashMap<>();
Car car = new Car();
car.setCarColor("红色");
car.setCarDischarge("好看");
hashMap.put("car", car);
hashMap.put("name","zhangsan");
hashMap.put("age","18");
return hashMap;