title: How can I set correct Last-Modified header value for Spring Web Service that is cached using Spring Cache?
body: <p>I have such Spring MVC Controller:</p>
  
  <pre><code>@Controller
  @RequestMapping(value = "/user")
  public class UserController {
     .....      
     @Cacheable(value = "users", key = "#id")
     @RequestMapping(value = "/get", method = RequestMethod.GET)
     @ResponseBody
     public User getUser(Long id){
         return userService.get(id);
     }
     ....
  }
  </code></pre>
  
  <p>I want to add header Last-Modified to HTTP Response of GetUser web service.<br>
  How can I get proper date when cache was added to my store?<br>
  How can I add header Last-Modified with this date to response of my Spring Controller Method?</p>