Package org.apache.flink.table.runtime.operators.rank.window.combines

Class TopNRecordsCombiner

java.lang.Object

org.apache.flink.table.runtime.operators.rank.window.combines.TopNRecordsCombiner

All Implemented Interfaces:

RecordsCombiner

public final class TopNRecordsCombiner
extends Object
implements RecordsCombiner

An implementation of RecordsCombiner that save topN records of incremental input records into the window state.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	TopNRecordsCombiner.Factory	Factory to create TopNRecordsCombiner.

Nested classes/interfaces inherited from interface org.apache.flink.table.runtime.operators.window.tvf.combines.RecordsCombiner

RecordsCombiner.LocalFactory

Constructor Summary

Constructors

Constructor

Description

TopNRecordsCombiner(WindowTimerService<Long> timerService, StateKeyContext keyContext, WindowMapState<Long,List<org.apache.flink.table.data.RowData>> dataState, Comparator<org.apache.flink.table.data.RowData> sortKeyComparator, org.apache.flink.api.java.functions.KeySelector<org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData> sortKeySelector, long topN, org.apache.flink.api.common.typeutils.TypeSerializer<org.apache.flink.table.data.RowData> recordSerializer, boolean isEventTime)

Method Summary

Modifier and Type	Method	Description
void	close()	Release resources allocated by this combine function.
void	combine(WindowKey windowKey, Iterator<org.apache.flink.table.data.RowData> records)	Combines the buffered data into state based on the given window-key pair.

Methods inherited from class java.lang.Object

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

Constructor Detail

TopNRecordsCombiner

public TopNRecordsCombiner(WindowTimerService<Long> timerService,
                           StateKeyContext keyContext,
                           WindowMapState<Long,List<org.apache.flink.table.data.RowData>> dataState,
                           Comparator<org.apache.flink.table.data.RowData> sortKeyComparator,
                           org.apache.flink.api.java.functions.KeySelector<org.apache.flink.table.data.RowData,org.apache.flink.table.data.RowData> sortKeySelector,
                           long topN,
                           org.apache.flink.api.common.typeutils.TypeSerializer<org.apache.flink.table.data.RowData> recordSerializer,
                           boolean isEventTime)

Method Detail

combine

public void combine(WindowKey windowKey,
                    Iterator<org.apache.flink.table.data.RowData> records)
             throws Exception

Description copied from interface: RecordsCombiner

Combines the buffered data into state based on the given window-key pair.

Specified by:

combine in interface RecordsCombiner

Parameters:

windowKey - the window-key pair that the buffered data belong to, the window-key object is reused.

records - the buffered data, the iterator and RowData objects are reused.

Throws:

Exception

close

public void close()
           throws Exception

Description copied from interface: RecordsCombiner

Release resources allocated by this combine function.

Specified by:

close in interface RecordsCombiner

Throws:

Exception