org.apache.storm.task

Class TopologyContext

java.lang.Object

org.apache.storm.task.TopologyContext

public class TopologyContext
extends java.lang.Object

A TopologyContext is given to bolts and spouts in their "prepare" and "open" methods, respectively. This object provides information about the component's place within the topology, such as task ids, inputs and outputs, etc.

The TopologyContext is also used to declare ISubscribedState objects to synchronize state with StateSpouts this object is subscribed to.

Constructor Summary

Constructors

Constructor and Description
TopologyContext(TaskContext t2TaskContext)

Method Summary

Modifier and Type	Method and Description
java.lang.String	getThisComponentId()
java.util.Map<GlobalStreamId,java.lang.Object>	getThisSources() Gets the declared inputs to this component.
java.util.Set<java.lang.String>	getThisStreams() Gets the set of streams declared for the component of this task.
int	getThisTaskId()
void	setTempBoltDeclarer(Twister2BoltDeclarer t2bd) This method will be temporary used to extract parameter that are not yest supported by TaskContext

Methods inherited from class java.lang.Object

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

Constructor Detail

TopologyContext

public TopologyContext(TaskContext t2TaskContext)

Method Detail

getThisTaskId

public int getThisTaskId()

getThisComponentId

public java.lang.String getThisComponentId()

setTempBoltDeclarer

public void setTempBoltDeclarer(Twister2BoltDeclarer t2bd)

This method will be temporary used to extract parameter that are not yest supported by TaskContext

getThisStreams

public java.util.Set<java.lang.String> getThisStreams()

Gets the set of streams declared for the component of this task.

getThisSources

public java.util.Map<GlobalStreamId,java.lang.Object> getThisSources()

Gets the declared inputs to this component. todo the return type of this method should be Map<GlobalStreamId, Grouping>, where Grouping is a thrift object. So changing it to Object, just to support windowing. WindowedBoltExecutor just need the GlobalStreamId

Returns:

A map from subscribed component/stream to the grouping subscribed with.