Question

How can I set a session object which I can use then in any of my views by using ${variable} or ${requestScope.variable}

To be able to use sessions do I need to set <%@ page session="true" %> ?

Answer 1

If you want to access a session variable in your view the easiest way to do it is :

${sessionScope.yourVariable} 

See the Using Scope Objects for more info.

If you set <%@ page session="true"> then the JSP will merge the session scope and at the page scope into a single namespace. Then you can do:

${yourVariable}

You can put something into the session in a mvc controller like this:

@RequestMapping("/test")
@Controller
public class TestController {
    @RequestMapping(method = RequestMethod.GET)
    public String testMestod(HttpServletRequest request)
    {
        request.getSession().setAttribute("testVariable", "Test Values!!");
        return "testJsp";
    }
}

Finally, the @SessionAttribute is meant for a specifc use case, and doesn’t put variables into the session so that anyone can access them:

Here is how the spring folks describe the functionality of @SessionAttribute:

The @SessionAttributes works in the
same way as the sessionForm of the
SimpleFormController. It puts the
command (or for the @SessionAttributes
any object) in the session for the
duration between the first and the
last request (most of the time the
initial GET and the final POST). After
that the stuff is removed.

Each Controller has it’s own ModelMap
so something put as a
@SessionAttributes in controller1
isn’t available in controller2 and
vice versa. For that to work you will
have to put stuff on the session
manually yourself.