| Interface | Description | 
|---|---|
| StateDelegator | The  StateDelegatoris able to delegateBeamFnApi.StateRequests to a set of registered
 handlers. | 
| StateDelegator.Registration | Allows callers to deregister from receiving further state requests. | 
| StateRequestHandler | Handler for  StateRequests. | 
| StateRequestHandlers.BagUserStateHandler<K,V,W extends BoundedWindow> | A handler for bag user state. | 
| StateRequestHandlers.BagUserStateHandlerFactory<K,V,W extends BoundedWindow> | A factory which constructs  StateRequestHandlers.BagUserStateHandlers. | 
| StateRequestHandlers.IterableSideInputHandler<V,W extends BoundedWindow> | A handler for iterable side inputs. | 
| StateRequestHandlers.MultimapSideInputHandler<K,V,W extends BoundedWindow> | A handler for multimap side inputs. | 
| StateRequestHandlers.SideInputHandler | Marker interface that denotes some type of side input handler. | 
| StateRequestHandlers.SideInputHandlerFactory | A factory which constructs  StateRequestHandlers.MultimapSideInputHandlers. | 
| Class | Description | 
|---|---|
| GrpcStateService | An implementation of the Beam Fn State service. | 
| InMemoryBagUserStateFactory<K,V,W extends BoundedWindow> | Holds user state in memory. | 
| StateRequestHandlers | A set of utility methods which construct  StateRequestHandlers. |