| Package | Description | 
|---|---|
| org.apache.storm.streams | |
| org.apache.storm.streams.operations | 
| Modifier and Type | Method and Description | 
|---|---|
| <R> Stream<R> | Stream. aggregate(R initialValue,
         BiFunction<? super R,? super T,? extends R> accumulator,
         BiFunction<? super R,? super R,? extends R> combiner)Aggregates the values in this stream using the given initial value, accumulator and combiner. | 
| <R> Stream<R> | Stream. aggregate(R initialValue,
         BiFunction<? super R,? super T,? extends R> accumulator,
         BiFunction<? super R,? super R,? extends R> combiner)Aggregates the values in this stream using the given initial value, accumulator and combiner. | 
| <R> PairStream<K,R> | PairStream. aggregateByKey(R initialValue,
              BiFunction<? super R,? super V,? extends R> accumulator,
              BiFunction<? super R,? super R,? extends R> combiner)Aggregates the values for each key of this stream using the given initial value, accumulator and combiner. | 
| <R> PairStream<K,R> | PairStream. aggregateByKey(R initialValue,
              BiFunction<? super R,? super V,? extends R> accumulator,
              BiFunction<? super R,? super R,? extends R> combiner)Aggregates the values for each key of this stream using the given initial value, accumulator and combiner. | 
| <R> StreamState<K,R> | PairStream. updateStateByKey(R initialValue,
                BiFunction<? super R,? super V,? extends R> stateUpdateFn)Update the state by applying the given state update function to the previous state of the key and the new value for the key. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | Reducer<T>The  Reducerperforms an operation on two values of the same type producing a result of the same type. | 
| Modifier and Type | Method and Description | 
|---|---|
| static <T,R> CombinerAggregator<T,R,R> | CombinerAggregator. of(R initialValue,
  BiFunction<? super R,? super T,? extends R> accumulator,
  BiFunction<? super R,? super R,? extends R> combiner)A static factory to create a  CombinerAggregatorbased on initial value, accumulator and combiner. | 
| static <T,R> CombinerAggregator<T,R,R> | CombinerAggregator. of(R initialValue,
  BiFunction<? super R,? super T,? extends R> accumulator,
  BiFunction<? super R,? super R,? extends R> combiner)A static factory to create a  CombinerAggregatorbased on initial value, accumulator and combiner. | 
| static <T,S> StateUpdater<T,S> | StateUpdater. of(S initialValue,
  BiFunction<? super S,? super T,? extends S> stateUpdateFn)A static factory to create a  StateUpdaterbased on an initial value of the state and a state update function. | 
Copyright © 2022 The Apache Software Foundation. All rights reserved.