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"}}'