org.apache.flink.streaming.api.windowing.evictors

接口 Evictor<T,W extends Window>

类型参数:

T - The type of elements that this Evictor can evict.

W - The type of Windows on which this Evictor can operate.

所有超级接口:

Serializable

所有已知实现类:

CountEvictor, DeltaEvictor, TimeEvictor

@PublicEvolving
public interface Evictor<T,W extends Window>
extends Serializable

An Evictor can remove elements from a pane before/after the evaluation of WindowFunction and after the window evaluation gets triggered by a Trigger

A pane is the bucket of elements that have the same key (assigned by the KeySelector) and same Window. An element can be in multiple panes of it was assigned to multiple windows by the WindowAssigner. These panes all have their own instance of the Evictor.

嵌套类概要

嵌套类

限定符和类型	接口和说明
static interface	Evictor.EvictorContext A context object that is given to Evictor methods.

方法概要

限定符和类型	方法和说明
void	evictAfter(Iterable<TimestampedValue<T>> elements, int size, W window, Evictor.EvictorContext evictorContext) Optionally evicts elements.
void	evictBefore(Iterable<TimestampedValue<T>> elements, int size, W window, Evictor.EvictorContext evictorContext) Optionally evicts elements.

方法详细资料

evictBefore

void evictBefore(Iterable<TimestampedValue<T>> elements,
                 int size,
                 W window,
                 Evictor.EvictorContext evictorContext)

Optionally evicts elements. Called before windowing function.

参数:

elements - The elements currently in the pane.

size - The current number of elements in the pane.

window - The Window

evictorContext - The context for the Evictor

evictAfter

void evictAfter(Iterable<TimestampedValue<T>> elements,
                int size,
                W window,
                Evictor.EvictorContext evictorContext)

Optionally evicts elements. Called after windowing function.

参数:

elements - The elements currently in the pane.

size - The current number of elements in the pane.

window - The Window

evictorContext - The context for the Evictor