io.aeron.samples.cluster.tutorial

Class BasicAuctionClusteredService

java.lang.Object

io.aeron.samples.cluster.tutorial.BasicAuctionClusteredService

All Implemented Interfaces:

ClusteredService

public class BasicAuctionClusteredService
extends Object
implements ClusteredService

Auction service implementing the business logic.

Field Summary

Fields

Modifier and Type	Field and Description
static int	BID_MESSAGE_LENGTH
static int	BID_SUCCEEDED_OFFSET
static int	CORRELATION_ID_OFFSET
static int	CUSTOMER_ID_OFFSET
static int	EGRESS_MESSAGE_LENGTH
static int	PRICE_OFFSET
static int	SNAPSHOT_CUSTOMER_ID_OFFSET
static int	SNAPSHOT_MESSAGE_LENGTH
static int	SNAPSHOT_PRICE_OFFSET

Constructor Summary

Constructors

Constructor and Description
BasicAuctionClusteredService()

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object o)
int	hashCode()
void	onRoleChange(Cluster.Role newRole) Notify that the cluster node has changed role.
void	onSessionClose(ClientSession session, long timestamp, CloseReason closeReason) A session has been closed for a client to the cluster.
void	onSessionMessage(ClientSession session, long timestamp, DirectBuffer buffer, int offset, int length, Header header) A message has been received to be processed by a clustered service.
void	onSessionOpen(ClientSession session, long timestamp) A session has been opened for a client to the cluster.
void	onStart(Cluster cluster, Image snapshotImage) Start event for the service where the service can perform any initialisation required and load snapshot state.
void	onTakeSnapshot(ExclusivePublication snapshotPublication) The service should take a snapshot and store its state to the provided archive Publication.
void	onTerminate(Cluster cluster) Called when the container is going to terminate.
void	onTimerEvent(long correlationId, long timestamp) A scheduled timer has expired.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface io.aeron.cluster.service.ClusteredService

onNewLeadershipTermEvent

Field Detail

CORRELATION_ID_OFFSET

public static final int CORRELATION_ID_OFFSET

See Also:

Constant Field Values

CUSTOMER_ID_OFFSET

public static final int CUSTOMER_ID_OFFSET

See Also:

Constant Field Values

PRICE_OFFSET

public static final int PRICE_OFFSET

See Also:

Constant Field Values

BID_MESSAGE_LENGTH

public static final int BID_MESSAGE_LENGTH

See Also:

Constant Field Values

BID_SUCCEEDED_OFFSET

public static final int BID_SUCCEEDED_OFFSET

See Also:

Constant Field Values

EGRESS_MESSAGE_LENGTH

public static final int EGRESS_MESSAGE_LENGTH

See Also:

Constant Field Values

SNAPSHOT_CUSTOMER_ID_OFFSET

public static final int SNAPSHOT_CUSTOMER_ID_OFFSET

See Also:

Constant Field Values

SNAPSHOT_PRICE_OFFSET

public static final int SNAPSHOT_PRICE_OFFSET

See Also:

Constant Field Values

SNAPSHOT_MESSAGE_LENGTH

public static final int SNAPSHOT_MESSAGE_LENGTH

See Also:

Constant Field Values

Constructor Detail

BasicAuctionClusteredService

public BasicAuctionClusteredService()

Method Detail

onStart

public void onStart(Cluster cluster,
                    Image snapshotImage)

Description copied from interface: ClusteredService

Start event for the service where the service can perform any initialisation required and load snapshot state. The snapshot image can be null if no previous snapshot exists.

Note: As this is a potentially long running operation the implementation should use Cluster.idleStrategy() and then occasionally call IdleStrategy.idle() or IdleStrategy.idle(int), especially when polling the Image returns 0.

Specified by:

onStart in interface ClusteredService

Parameters:

cluster - with which the service can interact.

snapshotImage - from which the service can load its archived state which can be null when no snapshot.

onSessionMessage

public void onSessionMessage(ClientSession session,
                             long timestamp,
                             DirectBuffer buffer,
                             int offset,
                             int length,
                             Header header)

Description copied from interface: ClusteredService

A message has been received to be processed by a clustered service.

Specified by:

onSessionMessage in interface ClusteredService

Parameters:

session - for the client which sent the message. This can be null if the client was a service.

timestamp - for when the message was received.

buffer - containing the message.

offset - in the buffer at which the message is encoded.

length - of the encoded message.

header - aeron header for the incoming message.

onTakeSnapshot

public void onTakeSnapshot(ExclusivePublication snapshotPublication)

Description copied from interface: ClusteredService

The service should take a snapshot and store its state to the provided archive Publication.

Note: As this is a potentially long running operation the implementation should use Cluster.idleStrategy() and then occasionally call IdleStrategy.idle() or IdleStrategy.idle(int), especially when the snapshot ExclusivePublication returns Publication.BACK_PRESSURED.

Specified by:

onTakeSnapshot in interface ClusteredService

Parameters:

snapshotPublication - to which the state should be recorded.

onRoleChange

public void onRoleChange(Cluster.Role newRole)

Description copied from interface: ClusteredService

Notify that the cluster node has changed role.

Specified by:

onRoleChange in interface ClusteredService

Parameters:

newRole - that the node has assumed.

onTerminate

public void onTerminate(Cluster cluster)

Description copied from interface: ClusteredService

Called when the container is going to terminate.

Specified by:

onTerminate in interface ClusteredService

Parameters:

cluster - with which the service can interact.

onSessionOpen

public void onSessionOpen(ClientSession session,
                          long timestamp)

Description copied from interface: ClusteredService

A session has been opened for a client to the cluster.

Specified by:

onSessionOpen in interface ClusteredService

Parameters:

session - for the client which have been opened.

timestamp - at which the session was opened.

onSessionClose

public void onSessionClose(ClientSession session,
                           long timestamp,
                           CloseReason closeReason)

Description copied from interface: ClusteredService

A session has been closed for a client to the cluster.

Specified by:

onSessionClose in interface ClusteredService

Parameters:

session - that has been closed.

timestamp - at which the session was closed.

closeReason - the session was closed.

onTimerEvent

public void onTimerEvent(long correlationId,
                         long timestamp)

Description copied from interface: ClusteredService

A scheduled timer has expired.

Specified by:

onTimerEvent in interface ClusteredService

Parameters:

correlationId - for the expired timer.

timestamp - at which the timer expired.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object