java - Spring MVC How take the parameter value of a GET HTTP Request in my controller method?

Question

In this period I am studing the Spring MVC showcase example (downloadable from STS dasboard) and I have some simple question about the Request Mapping examples:

1) In my home.jsp page I have this link:

        <li>
            <a id="byParameter" class="textLink" href="<c:url value="/mapping/parameter?foo=bar" />">By path, method, and presence of parameter</a>
        </li>

As you can see by this link I am doing an HTTP GET Request having a "foo" parameter containing the value: "bar".

This HTTP Request is handled by the following method of the controller class MappingController:

@RequestMapping(value="/mapping/parameter", method=RequestMethod.GET, params="foo")
public @ResponseBody String byParameter() {
    return "Mapped by path + method + presence of query parameter! (MappingController)";
}

This method manage HTTP Request (only GET type) that have a parameter named "foo"

How can I take the value ("bar") of this parameter and put it in a variable inside the code of my by Parameter method?

Answer 1

As explained in the documentation, by using an @RequestParam annotation:

public @ResponseBody String byParameter(@RequestParam("foo") String foo) {
    return "Mapped by path + method + presence of query parameter! (MappingController) - foo = "
           + foo;
}