Package org.apache.storm.state

Interface State

All Known Subinterfaces:
KeyValueState<K,V>
All Known Implementing Classes:
InMemoryKeyValueState, RedisKeyValueState
public interface State
The state of the component that is either managed by the framework (e.g in case of IStatefulBolt) or managed by the the individual components themselves.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    commit()
    Persist the current state.
    void
    commit(long txid)
    Commit a previously prepared transaction.
    void
    prepareCommit(long txid)
    Invoked by the framework to prepare a transaction for commit.
    void
    rollback()
    Rollback a prepared transaction to the previously committed state.

  • Method Details

    • prepareCommit

      void prepareCommit(long txid)
      Invoked by the framework to prepare a transaction for commit. It should be possible to commit the prepared state later.

      The same txid can be prepared again, but the next txid cannot be prepared when previous one is not yet committed.

      Parameters:
      txid - the transaction id

    • commit

      void commit(long txid)
      Commit a previously prepared transaction. It should be possible to retrieve a committed state later.
      Parameters:
      txid - the transaction id

    • commit

      void commit()
      Persist the current state. This is used when the component manages the state.

    • rollback

      void rollback()
      Rollback a prepared transaction to the previously committed state.