title: NullPointer exception in scheduled method
body: <p>I want to insert some data into my DB. But I catch </p>
  
  <pre><code>"ERROR: org.springframework.scheduling.support.TaskUtils$LoggingErrorHandler - Unexpected error occurred in scheduled task.
  java.lang.NullPointerException"
  </code></pre>
  
  <p>I don't know what to do.</p>
  
  <pre><code>public class HeadHunterImport {
      @Autowired
      private static HeadHunterService headHunterService;
  
  
      @Scheduled(fixedRate = 600000)
  
      public void AsyncRemovalOldData() {
          headHunterService.addHeadHunter("Moscow", 100, 100) ;  
  
      }
  </code></pre>
  
  <p>If I'll call it in controller it will work fine. What's wrong? </p>