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/OpenJDK 25

Interface Gatherer.Downstream<T>

Type Parameters:
T - the type of elements this downstream accepts
Enclosing interface:
Gatherer<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>
A Downstream object is the next stage in a pipeline of operations, to which elements can be sent.
Since:
24

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

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/Gatherer.Downstream.html