Module java.base

Package java.util.stream

Interface Gatherer.Downstream<T>

Type Parameters:

T - the type of elements this downstream accepts

Enclosing interface:

GathererPREVIEW<T,A,R>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public static interface Gatherer.Downstream<T>

Downstream is a preview API of the Java platform.

Programs can only use Downstream when preview features are enabled.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

A Downstream object is the next stage in a pipeline of operations, to which elements can be sent.

Since:

22

Method Summary

Modifier and Type	Method	Description
default boolean	isRejecting()	Checks whether the next stage is known to not want any more elements sent to it.
boolean	push(T element)	Pushes, if possible, the provided element downstream -- to the next stage in the pipeline.

Method Details

push

boolean push(T element)

Pushes, if possible, the provided element downstream -- to the next stage in the pipeline.

Implementation Requirements:

If this method returns false then no further elements will be accepted and subsequent invocations of this method will return false.

Parameters:

element - the element to push downstream

Returns:

true if more elements can be sent, and false if not.

isRejecting

default boolean isRejecting()

Checks whether the next stage is known to not want any more elements sent to it.

API Note:

This is best-effort only, once this returns true it should never return false again for the same instance.

Implementation Requirements:

The implementation in this interface returns false.

Returns:

true if this Downstream is known not to want any more elements sent to it, false if otherwise