backtype.storm.transactional
Interface ITransactionalSpout<T>

All Superinterfaces:

IComponent, Serializable

All Known Subinterfaces:

ICommitterTransactionalSpout<X>

All Known Implementing Classes:

BaseTransactionalSpout, OpaquePartitionedTransactionalSpoutExecutor, PartitionedTransactionalSpoutExecutor

public interface ITransactionalSpout<T>
extends IComponent

Nested Class Summary

static interface	ITransactionalSpout.Coordinator<X>
static interface	ITransactionalSpout.Emitter<X>

Method Summary

ITransactionalSpout.Coordinator<T>	getCoordinator(Map conf, TopologyContext context) The coordinator for a TransactionalSpout runs in a single thread and indicates when batches of tuples should be emitted and when transactions should commit.
ITransactionalSpout.Emitter<T>	getEmitter(Map conf, TopologyContext context) The emitter for a TransactionalSpout runs as many tasks across the cluster.

Methods inherited from interface backtype.storm.topology.IComponent

declareOutputFields, getComponentConfiguration

Method Detail

getCoordinator

ITransactionalSpout.Coordinator<T> getCoordinator(Map conf,
                                                  TopologyContext context)

The coordinator for a TransactionalSpout runs in a single thread and indicates when batches of tuples should be emitted and when transactions should commit. The Coordinator that you provide in a TransactionalSpout provides metadata for each transaction so that the transactions can be replayed.

getEmitter

ITransactionalSpout.Emitter<T> getEmitter(Map conf,
                                          TopologyContext context)

The emitter for a TransactionalSpout runs as many tasks across the cluster. Emitters are responsible for emitting batches of tuples for a transaction and must ensure that the same batch of tuples is always emitted for the same transaction id.