org.apache.flink.runtime.io.network.gates

Class Gate<T extends IOReadableWritable>

java.lang.Object

org.apache.flink.runtime.io.network.gates.Gate<T>

Type Parameters:

T - the record type to be transported from this gate TODO refactor with changes to input side

Direct Known Subclasses:

InputGate, OutputGate

public abstract class Gate<T extends IOReadableWritable>
extends Object

In Nephele a gate represents the connection between a user program and the processing framework. A gate must be connected to exactly one record reader/writer and to at least one channel. The Gate class itself is abstract. A gate automatically created for every record reader/writer in the user program. A gate can only be used to transport one specific type of records.

This class in general is not thread-safe.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Gate(JobID jobID, GateID gateID, int index) Constructs a new abstract gate

Method Summary

Methods

Modifier and Type	Method and Description
void	deliverEvent(AbstractTaskEvent event)
ChannelType	getChannelType()
protected EventNotificationManager	getEventNotificationManager() Returns the event notification manager used to dispatch events.
GateID	getGateID()
int	getIndex()
JobID	getJobID()
abstract boolean	isClosed() Checks if the gate is closed.
abstract boolean	isInputGate() Checks if the considered gate is an input gate.
abstract void	publishEvent(AbstractEvent event) Publishes an event.
abstract void	releaseAllChannelResources() Releases the allocated resources (particularly buffer) of all channels attached to this gate.
void	setChannelType(ChannelType channelType)
void	subscribeToEvent(EventListener eventListener, Class<? extends AbstractTaskEvent> eventType)
String	toString()
void	unsubscribeFromEvent(EventListener eventListener, Class<? extends AbstractTaskEvent> eventType)

Methods inherited from class java.lang.Object

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

Constructor Detail

Gate

protected Gate(JobID jobID,
    GateID gateID,
    int index)

Constructs a new abstract gate

Parameters:

jobID - the ID of the job this gate belongs to

gateID - the ID of this gate

index - the index of the gate in the list of available input/output gates.

Method Detail

getIndex

public final int getIndex()

getEventNotificationManager

protected final EventNotificationManager getEventNotificationManager()

Returns the event notification manager used to dispatch events.

Returns:

the event notification manager used to dispatch events

toString

public String toString()

Overrides:

toString in class Object

subscribeToEvent

public final void subscribeToEvent(EventListener eventListener,
                    Class<? extends AbstractTaskEvent> eventType)

unsubscribeFromEvent

public final void unsubscribeFromEvent(EventListener eventListener,
                        Class<? extends AbstractTaskEvent> eventType)

deliverEvent

public final void deliverEvent(AbstractTaskEvent event)

setChannelType

public final void setChannelType(ChannelType channelType)

getChannelType

public final ChannelType getChannelType()

getJobID

public JobID getJobID()

getGateID

public GateID getGateID()

publishEvent

public abstract void publishEvent(AbstractEvent event)
                           throws IOException,
                                  InterruptedException

Publishes an event.

Parameters:

event - the event to be published

Throws:

IOException - thrown if an error occurs while transmitting the event

InterruptedException - thrown if the thread is interrupted while waiting for the event to be published

releaseAllChannelResources

public abstract void releaseAllChannelResources()

Releases the allocated resources (particularly buffer) of all channels attached to this gate. This method should only be called after the respected task has stopped running.

isClosed

public abstract boolean isClosed()
                          throws IOException,
                                 InterruptedException

Checks if the gate is closed. The gate is closed if all this associated channels are closed.

Returns:

true if the gate is closed, false otherwise

Throws:

IOException - thrown if any error occurred while closing the gate

InterruptedException - thrown if the gate is interrupted while waiting for this operation to complete

isInputGate

public abstract boolean isInputGate()

Checks if the considered gate is an input gate.

Returns:

true if the considered gate is an input gate, false if it is an output gate