Spring MVC incoming parameters @RequestParam String requestedURL

Question

I have two Spring MVC actions that in this example takes one parameter from a form when submitted:

public ModelAndView login(HttpServletResponse response, HttpServletRequest request,  
@RequestParam String requestedURL )

I would like to know if the attribute requestedURL can refer to a declared variable that actually hold the name of the incoming attribute input name="requestURL" ...

class Core {
     static String requestedURL = "requestedURL"; 
}

pseudo code:

public ModelAndView login(..., @RequestParam String @ReadFrom(Core.RequestedURL) )

Notice the @ReadFrom

This is to avoid redundancy. Right now it is called requestedURL but in the future someone might want to change the input parameter name, this shouldn't be a hardcoded string in the applicaton in my opinion.

and

<input name="<%= Core.requestedURL %>" value="<%= requestedURL %>" />

and is read in the method when submitted. But does the attribute name have to be hardcoded in the incoming parameter of the action method?

Thanks!

mjs · Accepted Answer · 2012-08-03 13:24:19Z

1

Yes, it has to be hardcoded as part of the @RequestParam annotation - either hardcoded or refer to a static final variable.

The alternative is to take in a Model/Map as an additional parameter in the method and getting the attribute from that:

public ModelAndView login(HttpServletResponse response, HttpServletRequest request,  
Model model ){
    String requestedURL = model.asMap().get(Core.requestedURL);
}

Update You can refer to a static final variable this way: assuming:

public abstract class Core {
     public static final String requestedURL = "requestedURL"; 
}

public ModelAndView login(..., @RequestParam(Core.requestedURL) String requestedURL)

edited Aug 3, 2012 at 13:24

mjs

22.6k32 gold badges134 silver badges224 bronze badges

answered Aug 3, 2012 at 12:47

Biju Kunjummen

50.1k14 gold badges117 silver badges126 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

mjs Over a year ago

final works fine, actually mine is final. How would that look like if final ? otherwise your suggestion might be a nice workaround. Thanks!

mjs Over a year ago

I just looked into the RequestParam class. There is an attribute value="" ... what is this for? Says nothing about final..

Biju Kunjummen Over a year ago

I have added in an update - basically that is the attribute name to expect from the browser. The method parameter itself (requestedURL) gets changed after compilation(unless debug symbols are on), so the value attribute of @RequestParam is a way to show the name of the attribute

mjs Over a year ago

Ok! If the attribute is required=false, how would @RequestParam(..) look like? @RequestParam(value=Core.requestedURL, required=false) ??

Biju Kunjummen Over a year ago

Yes, that is correct, value() indicates the default that the annotation accepts, if only one parameter is provided that goes into the value attribute, if there are more than one, then you will have to specify the name like you have done.

Collectives™ on Stack Overflow

Spring MVC incoming parameters @RequestParam String requestedURL

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related