Autowiring HttpServletRequest in Spring controller

Question

Let's say I have a Spring controller.

@RequestMappin("/path")
public MyController {
}

As stated, default scope of the controller is Singleton. I know that I can autowire request in REQUEST scope beans, however, if I try to autowire request, so that

@RequestMappin("/path")
public MyController {
        @Autowired
        private HttpServletRequest request;
    }

It still works, and for each request I get appropriate request object. Does it mean that autowire works regardless the scope is request or not?

Tetragrammaton

Does this request is thread safe? I mean if there are attributes in this request , the value of the attribute is unique? – Orta

Answer 1

if it works that means spring doesn't inject exactly http request but a proxy. the proxy delegates calls to current http request

Xeroderma

So is this default behaviour, or with Reques scoped beans it injects request directly? – Tetragrammaton

i don't know. but it really should not matter - your program shouldn't rely on that – Xeroderma

Answer 2

When a spring web based application bootstraps, it will register the bean of type ServletRequest,ServletResponse,HttpSession,WebRequest with the support of ThreadLocal variables. So whenever you request one kind of above four, the actual value will be the actual stored ThreadLocal variable that are bound to the current thread.

You can find the details implementation mechanisms of @Autowired HttpServletRequest at @Autowired HttpServletRequest

Excepting

is it the reason we can do as following, to get the ServletRequest in an auto-wired bean to a controller like below? @Component public class PageModel { private HttpServletRequest request; public PageModel(HttpServletRequest request) { this.request = request; } if it works that means spring doesn't inject exactly http request but a proxy. the proxy delegates calls to current http request? – Afflatus

Answer 3

You can get HttpServletRequest object in each webservice method. Such as:

@RequestMapping("/method")
public void method(HttpServletRequest req) {
   // ...
}

Venicevenin

Answer 4

If you don't want to use @Autowired you can get HttpServletRequest in this way:

HttpServletRequest request = 
((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes())
.getRequest();

Sufficient