| Annotation Type | Description | 
|---|---|
| NonNull | A common Reactor annotation (similar to Spring ones) to declare that annotated elements
 cannot be  null. | 
| NonNullApi | A common Reactor annotation (similar to Spring one) to declare that parameters and return
 values are to be considered as non-nullable by default for a given package. | 
| Nullable | A common Reactor annotation (similar to Spring ones) to declare that annotated elements
 can be  nullunder some circumstance. |