Interface KeyValueState<K,V>

All Superinterfaces:
Iterable<Map.Entry<K,V>>, State
All Known Implementing Classes:
InMemoryKeyValueState, RedisKeyValueState

public interface KeyValueState<K,V> extends State, Iterable<Map.Entry<K,V>>
A state that supports key-value mappings.
  • Method Summary

    Modifier and Type
    Method
    Description
    delete(K key)
    Deletes the value mapped to the key, if there is any.
    get(K key)
    Returns the value mapped to the key.
    get(K key, V defaultValue)
    Returns the value mapped to the key or defaultValue if no mapping is found.
    void
    put(K key, V value)
    Maps the value with the key.

    Methods inherited from interface java.lang.Iterable

    forEach, iterator, spliterator

    Methods inherited from interface org.apache.storm.state.State

    commit, commit, prepareCommit, rollback
  • Method Details

    • put

      void put(K key, V value)
      Maps the value with the key.
      Parameters:
      key - the key
      value - the value
    • get

      V get(K key)
      Returns the value mapped to the key.
      Parameters:
      key - the key
      Returns:
      the value or null if no mapping is found
    • get

      V get(K key, V defaultValue)
      Returns the value mapped to the key or defaultValue if no mapping is found.
      Parameters:
      key - the key
      defaultValue - the value to return if no mapping is found
      Returns:
      the value or defaultValue if no mapping is found
    • delete

      V delete(K key)
      Deletes the value mapped to the key, if there is any.
      Parameters:
      key - the key