Package org.apache.flink.runtime.state

Interface KeyValueStateIterator

  • All Superinterfaces:
    AutoCloseable
    All Known Implementing Classes:
    HeapKeyValueStateIterator
    public interface KeyValueStateIterator
extends AutoCloseable
    Iterator that over all key-value state entries in a KeyedStateBackend. For use during snapshotting.

    This is required to partition all states into contiguous key-groups. The resulting iteration sequence is ordered by (key-group, kv-state).

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void close()  
      boolean isNewKeyGroup()
      Indicates if current key starts a new key-group, i.e. belong to a different key-group than it's predecessor.
      boolean isNewKeyValueState()
      Indicates if current key starts a new k/v-state, i.e. belong to a different k/v-state than it's predecessor.
      boolean isValid()
      Check if the iterator is still valid.
      byte[] key()  
      int keyGroup()
      Returns the key-group for the current key.
      int kvStateId()
      Returns the Id of the K/V state to which the current key belongs.
      void next()
      Advances the iterator.
      byte[] value()  

    • Method Detail

      • keyGroup

        int keyGroup()
        Returns the key-group for the current key.

      • key

        byte[] key()

      • value

        byte[] value()

      • kvStateId

        int kvStateId()
        Returns the Id of the K/V state to which the current key belongs.

      • isNewKeyValueState

        boolean isNewKeyValueState()
        Indicates if current key starts a new k/v-state, i.e. belong to a different k/v-state than it's predecessor.
        Returns:
        true iff the current key belong to a different k/v-state than it's predecessor.

      • isNewKeyGroup

        boolean isNewKeyGroup()
        Indicates if current key starts a new key-group, i.e. belong to a different key-group than it's predecessor.
        Returns:
        true iff the current key belong to a different key-group than it's predecessor.

      • isValid

        boolean isValid()
        Check if the iterator is still valid. Getters like key(), value(), etc. as well as next() should only be called if valid returned true. Should be checked after each call to next() before accessing iterator state.
        Returns:
        True iff this iterator is valid.