org.gridgain.grid.streamer.router

Class GridStreamerAffinityEventRouter

java.lang.Object

org.gridgain.grid.streamer.GridStreamerEventRouterAdapter

org.gridgain.grid.streamer.router.GridStreamerAffinityEventRouter

All Implemented Interfaces:

GridStreamerEventRouter

public class GridStreamerAffinityEventRouter
extends GridStreamerEventRouterAdapter

Router used to colocate identical streamer events or events with identical affinity key on the same node. Such collocation is often required to perform computations on multiple events together, for example, find number of occurrences of a word in some text. In this case you would collocate identical words together to make sure that you can update their counts.

Affinity Key

Affinity key for collocation of event together on the same node is specified via GridStreamerAffinityEventRouter.AffinityEvent.affinityKey() method. If event does not implement GridStreamerAffinityEventRouter.AffinityEvent interface, then event itself will be used to determine affinity.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	GridStreamerAffinityEventRouter.AffinityEvent All events that implement this interface will be routed based on key affinity.

Field Summary

Fields

Modifier and Type	Field and Description
static int	REPLICA_CNT

Constructor Summary

Constructors

Constructor and Description
GridStreamerAffinityEventRouter()

Method Summary

Methods

Modifier and Type	Method and Description
<T> GridNode	route(GridStreamerContext ctx, String stageName, T evt) Selects a node for given event that should be processed by a stage with given name.

Methods inherited from class org.gridgain.grid.streamer.GridStreamerEventRouterAdapter

route

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

REPLICA_CNT

public static final int REPLICA_CNT

See Also:

Constant Field Values

Constructor Detail

GridStreamerAffinityEventRouter

public GridStreamerAffinityEventRouter()

Method Detail

route

public <T> GridNode route(GridStreamerContext ctx,
                 String stageName,
                 T evt)

Selects a node for given event that should be processed by a stage with given name.

Parameters:

ctx - Streamer context.

stageName - Stage name.

evt - Event to route.

Returns:

Node to route to. If this method returns null then the whole pipeline execution will be terminated. All running and ongoing stages for pipeline execution will be cancelled.