difference between using and not using @modelAttribute in method parameter

Question

I am new to spring mvc and have seen examples where folks use @ModelAttribute("form") Person person in method parameter and some who just do (Person person). what is the difference.

Thanks in advance

Answer 1

@ModelAttribute allows you to specify the name of the model attribute. When parameter doesn't have this annotation, a decapitalized class name is used as an attribute name, i.e. Person p -> "person".

Answer 2

If you don't specify @ModelAttribute in this situation, then Spring will infer the presence of one. In this case, it would infer @ModelAttribute("person"). The argument is the name of the model.

If you don't want the default name, or if you just want to be explicit about saying that the Person parameter is a model attribute, then you should specify @ModelAttribute, with or without the explicit name.