Module net.pincette.rs

Package net.pincette.rs

Class Reducer

java.lang.Object

net.pincette.rs.Reducer

public class Reducer
extends Object

Functions to reduce a publisher and return the result as a CompletionStage.

Since:

1.1

Author:

Werner Donné

Method Summary

Modifier and Type	Method	Description
static <T> CompletionStage<Void>	forEach(Flow.Publisher<T> publisher, Consumer<T> consumer)	Runs consumer for each emitted value.
static <T> void	forEachJoin(Flow.Publisher<T> publisher, Consumer<T> consumer)	Runs consumer for each emitted value and makes it synchronous.
static <T> CompletionStage<Optional<T>>	reduce(Flow.Publisher<T> publisher, BinaryOperator<T> accumulator)	Accumulates all the values emitted by the publisher by combining them.
static <T, U> CompletionStage<U>	reduce(Flow.Publisher<T> publisher, Supplier<U> identity, BiFunction<U,T,U> accumulator)	Accumulates all the values emitted by the publisher into a new value.
static <T> Optional<T>	reduceJoin(Flow.Publisher<T> publisher, BinaryOperator<T> accumulator)	Accumulates all the values emitted by the publisher by combining them and makes it synchronous.
static <T, U> U	reduceJoin(Flow.Publisher<T> publisher, Supplier<U> identity, BiFunction<U,T,U> accumulator)	Accumulates all the values emitted by the publisher into a new value and makes it synchronous.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

forEach

public static <T> CompletionStage<Void> forEach(Flow.Publisher<T> publisher,
 Consumer<T> consumer)

Runs consumer for each emitted value.

Type Parameters:

T - the value type of the publisher.

Parameters:

publisher - the given publisher.

consumer - the consumer function.

Returns:

The completion stage.

Since:

1.4.1

forEachJoin

public static <T> void forEachJoin(Flow.Publisher<T> publisher,
 Consumer<T> consumer)

Runs consumer for each emitted value and makes it synchronous.

Type Parameters:

T - the value type of the publisher.

Parameters:

publisher - the given publisher.

consumer - the consumer function.

Since:

1.4.1

reduce

public static <T,
U> CompletionStage<U> reduce(Flow.Publisher<T> publisher,
 Supplier<U> identity,
 BiFunction<U,T,U> accumulator)

Accumulates all the values emitted by the publisher into a new value.

Type Parameters:

T - the value type of the publisher.

U - the value type of the result.

Parameters:

publisher - the given publisher.

identity - the function to produce the initial accumulated value.

accumulator - the function to accumulate all the values.

Returns:

The completion stage with the result.

Since:

1.1

reduce

public static <T> CompletionStage<Optional<T>> reduce(Flow.Publisher<T> publisher,
 BinaryOperator<T> accumulator)

Accumulates all the values emitted by the publisher by combining them.

Type Parameters:

T - the value type.

Parameters:

publisher - the given publisher.

accumulator - the associative function that combines the values.

Returns:

The completion stage with the result. The optional will be empty when the publisher didn't emit any values before completing.

Since:

1.1

reduceJoin

public static <T,
U> U reduceJoin(Flow.Publisher<T> publisher,
 Supplier<U> identity,
 BiFunction<U,T,U> accumulator)

Accumulates all the values emitted by the publisher into a new value and makes it synchronous.

Type Parameters:

T - the value type of the publisher.

U - the value type of the result.

Parameters:

publisher - the given publisher.

identity - the function to produce the initial accumulated value.

accumulator - the function to accumulate all the values.

Returns:

The completion stage with the result.

Since:

1.4.1

reduceJoin

public static <T> Optional<T> reduceJoin(Flow.Publisher<T> publisher,
 BinaryOperator<T> accumulator)

Accumulates all the values emitted by the publisher by combining them and makes it synchronous.

Type Parameters:

T - the value type.

Parameters:

publisher - the given publisher.

accumulator - the associative function that combines the values.

Returns:

The completion stage with the result. The optional will be empty when the publisher didn't emit any values before completing.

Since:

1.4.1