title: Controllers should be 'stateless', does having a final variable for the service object make this stateful?
body: <p>I am following best practices to enhance my codebase for my SpringBoot project and my controller classes conform to all the others but I am unsure if this would constitute statefulness as the service class is not subject to change, would this make it immutable?</p>
  <p>Example:</p>
  <pre><code>@RestController
  @RequestMapping(value = &quot;/users&quot;)
  public class UserController {
  
      final UserService userService;
  
      public UserController(UserService userService) {
          this.userService = userService;
      }
  }
  </code></pre>
  <p>The userService instance field is set to final and is instantiated in the controller's constructor method, does this mean the controller class breaches this best-practice and is stateful?</p>
  <p>Thanks</p>