Reports incorrect bean references in the scheduler parameter of the @Scheduled annotation.

Example:

  @Component public class UserController {...}
  @Component public class UserServiceAsyncTaskScheduler extends SimpleAsyncTaskScheduler {...}

  @Component public class UserService {
    @Scheduled(scheduler="userServiceAsyncTaskScheduler", cron="1 * * * * * ?")
    public void scheduleTask() {...}

    @Scheduled(scheduler="userController", cron="1 * * * * * ?") // reports "Bean must be one of these types: TaskScheduler,ScheduledExecutorService "
    public void scheduleTask_2() {...}

    @Scheduled(scheduler="unknown", cron="1 * * * * * ?")   // reports "Cannot resolve bean 'unknown'"
    public void scheduleTask_3() {...}
  }