org.gridgain.grid.streamer

Interface GridStreamerStage<IN>

All Known Implementing Classes:

GridStreamerStageWrapper

public interface GridStreamerStage<IN>

Streamer stage is a component that determines event processing flow. User logic related to any particular event processing is implemented by streamer stage. A stage takes events as an input and returns groups of events mapped to different stages as an output. Events for every returned stage will be passed to GridStreamerEventRouter which will determine on which node the stage should be executed.

Generally, event stage execution graph if fully controlled by return values of this method, while node execution graph is controlled by GridStreamerEventRouter.route(GridStreamerContext, String, Object) method.

Method Summary

Methods

Modifier and Type	Method and Description
String	name() Gets streamer stage name.
Map<String,Collection<?>>	run(GridStreamerContext ctx, Collection<IN> evts) Stage execution routine.

Method Detail

name

String name()

Gets streamer stage name.

Returns:

Name of the stage.

run

@Nullable
Map<String,Collection<?>> run(GridStreamerContext ctx,
                                     Collection<IN> evts)
                              throws GridException

Stage execution routine. After the passed in events are processed, stage can emit another set of events to be processed. The returned events can be mapped to different stages. Events for every returned stage will be passed to GridStreamerEventRouter which will determine on which node the stage should be executed.

Generally, event stage execution graph if fully controlled by return values of this method, while node execution graph is controlled by GridStreamerEventRouter.route(GridStreamerContext, String, Object) method.

Parameters:

ctx - Streamer context.

evts - Input events.

Returns:

Map of stage name to collection of events.

Throws:

GridException - If failed.