Spinner for Asynchronous and no spinner for Synchronous Observables

SpinnerNoSpinner.java

public class DataStore {
  
  public static Observable<Something> getSomethingObservable() {
      Something cachedSomething = MyCache.getCachedSomething();
      
      if (cachedSomething != null) {
        return Observable.just(cachedSomething); // still on same thread so returned to subscriber synchronously
      }
      
      return myRestService.getSomething(); // on separate Retrofit worker thread so returned to subscriber asynchronously
  }
  
}

public class SomethingActivity extends Activity {
  
  private Something mSomething;
  
  private void getAndDisplayData() {
    DataStore.getSomethingObservable()
      .observeOn(AndroidSchedulers.mainThread())
      .subscribe(something -> {
          mSomething = something;
          showSomething();
        });
    
    if (mSomething == null) {
      showSpinner(true);
    }
  }
  
  private void showSomething() {
    showSpinner(false);
    
    ...
  }
}