Package org.apache.storm.topology
Interface IStatefulComponent<T extends State>
- All Superinterfaces:
IComponent,Serializable
- All Known Subinterfaces:
IStatefulBolt<T>,IStatefulWindowedBolt<T>
- All Known Implementing Classes:
BaseStatefulBolt,BaseStatefulWindowedBolt,PersistentWindowedBoltExecutor,StatefulWindowedBoltExecutor,StatefulWordCounter
Common methods for stateful components in the topology.
A stateful component is one that has state (e.g. the result of some computation in a bolt) and wants the framework to manage its state.-
Method Summary
Modifier and TypeMethodDescriptionvoidThis method is invoked by the framework with the previously saved state of the component.voidpreCommit(long txid) This is a hook for the component to perform some actions just before the framework commits its state.voidprePrepare(long txid) This is a hook for the component to perform some actions just before the framework prepares its state.voidThis is a hook for the component to perform some actions just before the framework rolls back the prepared state.Methods inherited from interface org.apache.storm.topology.IComponent
declareOutputFields, getComponentConfiguration
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Method Details
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initState
This method is invoked by the framework with the previously saved state of the component. This is invoked after prepare but before the component starts processing tuples.- Parameters:
state- the previously saved state of the component.
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preCommit
void preCommit(long txid) This is a hook for the component to perform some actions just before the framework commits its state. -
prePrepare
void prePrepare(long txid) This is a hook for the component to perform some actions just before the framework prepares its state. -
preRollback
void preRollback()This is a hook for the component to perform some actions just before the framework rolls back the prepared state.
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