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

Class UnionInputGate

java.lang.Object

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

All Implemented Interfaces:

InputGate, InputGateListener

public class UnionInputGate
extends Object
implements InputGate, InputGateListener

Input gate wrapper to union the input from multiple input gates.

Each input gate has input channels attached from which it reads data. At each input gate, the input channels have unique IDs from 0 (inclusive) to the number of input channels (exclusive).

 +---+---+      +---+---+---+
 | 0 | 1 |      | 0 | 1 | 2 |
 +--------------+--------------+
 | Input gate 0 | Input gate 1 |
 +--------------+--------------+
 

The union input gate maps these IDs from 0 to the *total* number of input channels across all unioned input gates, e.g. the channels of input gate 0 keep their original indexes and the channel indexes of input gate 1 are set off by 2 to 2--4.

 +---+---++---+---+---+
 | 0 | 1 || 2 | 3 | 4 |
 +--------------------+
 | Union input gate   |
 +--------------------+
 

It is NOT possible to recursively union union input gates.

Constructor Summary

Constructors

Constructor and Description
UnionInputGate(InputGate... inputGates)

Method Summary

Modifier and Type	Method and Description
Optional<BufferOrEvent>	getNextBufferOrEvent() Blocking call waiting for next BufferOrEvent.
int	getNumberOfInputChannels() Returns the total number of input channels across all unioned input gates.
String	getOwningTaskName()
int	getPageSize()
boolean	isFinished()
void	notifyInputGateNonEmpty(InputGate inputGate) Notification callback if the input gate moves from zero to non-zero available input channels with data.
Optional<BufferOrEvent>	pollNextBufferOrEvent() Poll the BufferOrEvent.
void	registerListener(InputGateListener listener)
void	requestPartitions()
void	sendTaskEvent(TaskEvent event)

Methods inherited from class java.lang.Object

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

Constructor Detail

UnionInputGate

public UnionInputGate(InputGate... inputGates)

Method Detail

getNumberOfInputChannels

public int getNumberOfInputChannels()

Returns the total number of input channels across all unioned input gates.

Specified by:

getNumberOfInputChannels in interface InputGate

getOwningTaskName

public String getOwningTaskName()

Specified by:

getOwningTaskName in interface InputGate

isFinished

public boolean isFinished()

Specified by:

isFinished in interface InputGate

requestPartitions

public void requestPartitions()
                       throws IOException,
                              InterruptedException

Specified by:

requestPartitions in interface InputGate

Throws:

IOException

InterruptedException

getNextBufferOrEvent

public Optional<BufferOrEvent> getNextBufferOrEvent()
                                             throws IOException,
                                                    InterruptedException

Description copied from interface: InputGate

Blocking call waiting for next BufferOrEvent.

Specified by:

getNextBufferOrEvent in interface InputGate

Returns:

Optional.empty() if InputGate.isFinished() returns true.

Throws:

IOException

InterruptedException

pollNextBufferOrEvent

public Optional<BufferOrEvent> pollNextBufferOrEvent()
                                              throws UnsupportedOperationException

Description copied from interface: InputGate

Poll the BufferOrEvent.

Specified by:

pollNextBufferOrEvent in interface InputGate

Returns:

Optional.empty() if there is no data to return or if InputGate.isFinished() returns true.

Throws:

UnsupportedOperationException

sendTaskEvent

public void sendTaskEvent(TaskEvent event)
                   throws IOException

Specified by:

sendTaskEvent in interface InputGate

Throws:

IOException

registerListener

public void registerListener(InputGateListener listener)

Specified by:

registerListener in interface InputGate

getPageSize

public int getPageSize()

Specified by:

getPageSize in interface InputGate

notifyInputGateNonEmpty

public void notifyInputGateNonEmpty(InputGate inputGate)

Description copied from interface: InputGateListener

Notification callback if the input gate moves from zero to non-zero available input channels with data.

Specified by:

notifyInputGateNonEmpty in interface InputGateListener

Parameters:

inputGate - Input Gate that became available.