| Interface | Description | 
|---|---|
| AsyncStreamTask | An AsyncStreamTask is the basic class to support multithreading execution in Samza container. | 
| AsyncStreamTaskFactory | Build  AsyncStreamTaskinstances. | 
| ClosableTask | Deprecated | 
| EndOfStreamListenerTask | The EndOfStreamListenerTask augments  StreamTaskallowing the method implementor to specify code to be
 executed when the 'end-of-stream' is reached for all input SSPs. | 
| InitableTask | Used as an interface for user processing StreamTasks that need to have specific functionality performed as their StreamTasks
 are instantiated by TaskRunner. | 
| MessageCollector | Used as an interface for the means of sending message envelopes to an output stream. | 
| StreamOperatorTaskFactory | Build  AsyncStreamTaskinstances. | 
| StreamTask | A StreamTask is the basic class on which Samza jobs are implemented. | 
| StreamTaskFactory | Build  StreamTaskinstances. | 
| TaskCallback | A TaskCallback is fired by a  AsyncStreamTaskto notify when an asynchronous
 process has completed. | 
| TaskCoordinator | TaskCoordinators are provided to the process methods of  StreamTaskimplementations
 to allow the user code to request actions from the Samza framework, including committing the current checkpoints
 to configured org.apache.samza.checkpoint.CheckpointManager or shutting down the task or all tasks within
 a container. | 
| TaskFactory<T> | The base interface for all task factories (i.e. | 
| WindowableTask | Add-on interface to  StreamTaskimplementations to add code which will be run on
 a specified time interval (via configuration). | 
| Enum | Description | 
|---|---|
| TaskCoordinator.RequestScope | A task can make requests to the Samza framework while processing messages, such as
  TaskCoordinator.commit(RequestScope)andTaskCoordinator.shutdown(RequestScope). |