Java Spring boot: How do I Store random number in cache every hour?

I am trying to find a way to store a random value in the cache. When user get requests, it will Not call random number generate, but use the value stored. It will update the random generator every hour .

Is this the correct way to do this, or is there more efficient code?

@Service
class TestService {
 
  private int createRandomValue() {
      Random rand = new Random(); 
      int random_value = rand.nextInt(100); 
      return random_value;
  }

  @Cacheable(value = "randomvalue")
  public int getRandomValue() {
      return createRandomValue();
  }
   
 @CachePut(value = "randomvalue")
 @Scheduled(fixedDelay = 36000)
 public int updateRandomValue() {
      return createRandomValue();
 }
}

This isn't a spring specific answer, but start by creating a class variable that will store the value between calls, which we can do by moving int random_value out of the method and into the class, and returning it directly from the getRandomValue() method like so return random_value;.

All together it might look a bit like this:

@Service
class TestService {
  //Class variable
  private int random_value = 0;

  private int createRandomValue() {
      Random rand = new Random(); 
      //Update the class variable
      random_value = rand.nextInt(100); 
      return random_value;
  }

  @Cacheable(value = "randomvalue")
  public int getRandomValue() {
      //Return the stored class variable
      return random_value;
  }
   
  @CachePut(value = "randomvalue")
  @Scheduled(fixedDelay = 36000)
  public int updateRandomValue() {
      return createRandomValue();
  }
}