org.apache.flink.runtime.io.network.partition

Interface SubpartitionSelector<T>

Type Parameters:

T - data type that could be used to represent a subpartition.

All Known Implementing Classes:

RoundRobinSubpartitionSelector

public interface SubpartitionSelector<T>

SubpartitionSelector helps to choose from multiple available subpartitions when their output buffers should union into one stream.

Method Summary

Modifier and Type	Method and Description
T	getNextSubpartitionToConsume() Returns the next subpartition to consume data.
boolean	isMoreSubpartitionSwitchable() Whether the invoker can get a different subpartition in the next invocation of getNextSubpartitionToConsume().
void	markLastConsumptionStatus(boolean isDataAvailable, boolean isPartialRecord) Records the status of the last consumption attempt on the subpartition returned by the last invocation of getNextSubpartitionToConsume().
boolean	notifyDataAvailable(T subpartition) Marks a subpartition as having data available.

Method Detail

notifyDataAvailable

boolean notifyDataAvailable(T subpartition)

Marks a subpartition as having data available.

Returns:

true if this selector did not already contain the subpartition.

getNextSubpartitionToConsume

T getNextSubpartitionToConsume()

Returns the next subpartition to consume data.

markLastConsumptionStatus

void markLastConsumptionStatus(boolean isDataAvailable,
                               boolean isPartialRecord)

Records the status of the last consumption attempt on the subpartition returned by the last invocation of getNextSubpartitionToConsume().

This method must be invoked every time a subpartition acquired from this class is consumed.

Parameters:

isDataAvailable - whether the consumption returned a valid data.

isPartialRecord - whether the returned data contains partial record. Ignored if there was no data available.

isMoreSubpartitionSwitchable

boolean isMoreSubpartitionSwitchable()

Whether the invoker can get a different subpartition in the next invocation of getNextSubpartitionToConsume().