org.apache.storm.starter

Class StatefulTopology

java.lang.Object

org.apache.storm.starter.StatefulTopology

public class StatefulTopology
extends Object

An example topology that demonstrates the use of IStatefulBolt to manage state. To run the example,

 $ storm jar examples/storm-starter/storm-starter-topologies-*.jar storm.starter.StatefulTopology statetopology 

The default state used is ‘InMemoryKeyValueState’ which does not persist the state across restarts. You could use ‘RedisKeyValueState’ to test state persistence by setting below property in conf/storm.yaml

 topology.state.provider: org.apache.storm.redis.state.RedisKeyValueStateProvider 

You should also start a local redis instance before running the ‘storm jar’ command. The default RedisKeyValueStateProvider parameters can be overridden in conf/storm.yaml, for e.g.

 topology.state.provider.config: ‘{“keyClass”:“…”, “valueClass”:“…”,  “keySerializerClass”:“…”, “valueSerializerClass”:“…”,  “jedisPoolConfig”:{“host”:“localhost”, “port”:6379,  “timeout”:2000, “database”:0, “password”:“xyz”}}’

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StatefulTopology.PrinterBolt

Constructor Summary

Constructors

Constructor and Description
StatefulTopology()

Method Summary

Modifier and Type	Method and Description
static void	main(String[] args)

Methods inherited from class java.lang.Object

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

Constructor Detail

StatefulTopology

public StatefulTopology()

Method Detail

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception