Get UserDetails object from Security Context in Sp

问题:

I'm using Spring Security 3 and Spring MVC 3.05.

I would like to print username of currently logged in user,how can I fetch UserDetails in my Controller?

@RequestMapping(value="/index.html", method=RequestMethod.GET)
    public ModelAndView indexView(){
         UserDetails user = ?
                mv.addObject("username", user.getUsername());
        ModelAndView mv = new ModelAndView("index");
        return mv;
    }   

回答1:

If you already know for sure that the user is logged in (in your example if /index.html is protected):

UserDetails userDetails =
 (UserDetails)SecurityContextHolder.getContext().getAuthentication().getPrincipal();

To first check if the user is logged in, check that the current Authentication is not a AnonymousAuthenticationToken.

Authentication auth = SecurityContextHolder.getContext().getAuthentication();
if (!(auth instanceof AnonymousAuthenticationToken)) {
        // userDetails = auth.getPrincipal()
}

回答2:

Let Spring 3 injection take care of this.

Thanks to tsunade21 the easiest way is:

 @RequestMapping(method = RequestMethod.GET)   
 public ModelAndView anyMethodNameGoesHere(Principal principal) {
        final String loggedInUserName = principal.getName();

 }

回答3:

If you just want to print user name on the pages, maybe you'll like this solution. It's free from object castings and works without Spring Security too:

@RequestMapping(value = "/index.html", method = RequestMethod.GET)
public ModelAndView indexView(HttpServletRequest request) {

    ModelAndView mv = new ModelAndView("index");

    String userName = "not logged in"; // Any default user  name
    Principal principal = request.getUserPrincipal();
    if (principal != null) {
        userName = principal.getName();
    }

    mv.addObject("username", userName);

    // By adding a little code (same way) you can check if user has any
    // roles you need, for example:

    boolean fAdmin = request.isUserInRole("ROLE_ADMIN");
    mv.addObject("isAdmin", fAdmin);

    return mv;
}

Note "HttpServletRequest request" parameter added.

Works fine because Spring injects it's own objects (wrappers) for HttpServletRequest, Principal etc., so you can use standard java methods to retrieve user information.

回答4:

That's another solution (Spring Security 3):

public String getLoggedUser() throws Exception {
    String name = SecurityContextHolder.getContext().getAuthentication().getName();
    return (!name.equals("anonymousUser")) ? name : null;
}

回答5:

if you are using spring security then you can get the current logged in user by

Authentication auth = SecurityContextHolder.getContext().getAuthentication();
     String name = auth.getName(); //get logged in username