Class ChannelCoordinator

java.lang.Object

org.apache.catalina.tribes.group.ChannelInterceptorBase

org.apache.catalina.tribes.group.ChannelCoordinator

All Implemented Interfaces:

ChannelInterceptor, Heartbeat, MembershipListener, MessageListener

public class ChannelCoordinator
extends ChannelInterceptorBase
implements MessageListener

The channel coordinator object coordinates the membership service, the sender and the receiver. This is the last interceptor in the chain.

Nested Class Summary

Nested classes/interfaces inherited from interface ChannelInterceptor

ChannelInterceptor.InterceptorEvent

Field Summary

Fields

Modifier and Type	Field	Description
protected static final StringManager	sm	String manager for this class.

Fields inherited from class ChannelInterceptorBase

optionFlag

Constructor Summary

Constructors

Constructor	Description
ChannelCoordinator()	Default constructor.
ChannelCoordinator(ChannelReceiver receiver, ChannelSender sender, MembershipService service)	Construct a ChannelCoordinator with the specified receiver, sender and membership service.

Method Summary

Modifier and Type	Method	Description
boolean	accept(ChannelMessage msg)	Allows skipping processing of the specified message.
ChannelReceiver	getClusterReceiver()	Returns the cluster receiver.
ChannelSender	getClusterSender()	Returns the cluster sender.
Member	getLocalMember(boolean incAlive)	Intercepts the Channel.getLocalMember(boolean) method
Member	getMember(Member mbr)	Intercepts the Channel.getMember(Member) method
Member[]	getMembers()	Intercepts the Channel.getMembers() method
MembershipService	getMembershipService()	Returns the membership service.
boolean	hasMembers()	Intercepts the Channel.hasMembers() method
void	heartbeat()	The heartbeat() method gets invoked periodically to allow interceptors to clean up resources, time out object and perform actions that are unrelated to sending/receiving data.
protected void	internalStart(int svc)	Starts up the channel.
protected void	internalStop(int svc)	Shuts down the channel.
void	memberAdded(Member member)	A member was added to the group
void	memberDisappeared(Member member)	A member was removed from the group If the member left voluntarily, the Member.getCommand will contain the Member.SHUTDOWN_PAYLOAD data
void	messageReceived(ChannelMessage msg)	The messageReceived is invoked when a message is received.
void	sendMessage(Member[] destination, ChannelMessage msg, InterceptorPayload payload)	Send a message to one or more members in the cluster
void	setClusterReceiver(ChannelReceiver clusterReceiver)	Sets the cluster receiver.
void	setClusterSender(ChannelSender clusterSender)	Sets the cluster sender.
void	setMembershipService(MembershipService membershipService)	Sets the membership service.
void	start(int svc)	Starts up the channel.
void	stop(int svc)	Shuts down the channel.

Methods inherited from class ChannelInterceptorBase

fireInterceptorEvent, getChannel, getNext, getOptionFlag, getPrevious, okToProcess, setChannel, setNext, setOptionFlag, setPrevious

Methods inherited from class Object

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

Field Details

sm

protected static final StringManager sm

String manager for this class.

Constructor Details

ChannelCoordinator

public ChannelCoordinator()

Default constructor.

ChannelCoordinator

public ChannelCoordinator(ChannelReceiver receiver,
 ChannelSender sender,
 MembershipService service)

Construct a ChannelCoordinator with the specified receiver, sender and membership service.

Parameters:

receiver - The channel receiver

sender - The channel sender

service - The membership service

Method Details

sendMessage

public void sendMessage(Member[] destination,
 ChannelMessage msg,
 InterceptorPayload payload)
                 throws ChannelException

Send a message to one or more members in the cluster

Specified by:

sendMessage in interface ChannelInterceptor

Overrides:

sendMessage in class ChannelInterceptorBase

Parameters:

destination - Member[] - the destinations, null or zero length means all

msg - ClusterMessage - the message to send

payload - TBA

Throws:

ChannelException - if a serialization error happens.

See Also:

• ErrorHandler
• InterceptorPayload

start

public void start(int svc)
           throws ChannelException

Description copied from interface: ChannelInterceptor

Starts up the channel. This can be called multiple times for individual services to start The svc parameter can be the logical or value of any constants

Specified by:

start in interface ChannelInterceptor

Overrides:

start in class ChannelInterceptorBase

Parameters:

svc - one of:

• Channel.DEFAULT - will start all services
• Channel.MBR_RX_SEQ - starts the membership receiver
• Channel.MBR_TX_SEQ - starts the membership broadcaster
• Channel.SND_TX_SEQ - starts the replication transmitter
• Channel.SND_RX_SEQ - starts the replication receiver

Throws:

ChannelException - if a startup error occurs or the service is already started.

See Also:

• Channel

stop

public void stop(int svc)
          throws ChannelException

Description copied from interface: ChannelInterceptor

Shuts down the channel. This can be called multiple times for individual services to shut down. The svc parameter can be the logical or value of any constants

Specified by:

stop in interface ChannelInterceptor

Overrides:

stop in class ChannelInterceptorBase

Parameters:

svc - one of:

• Channel.DEFAULT - will shut down all services
• Channel.MBR_RX_SEQ - stops the membership receiver
• Channel.MBR_TX_SEQ - stops the membership broadcaster
• Channel.SND_TX_SEQ - stops the replication transmitter
• Channel.SND_RX_SEQ - stops the replication receiver

Throws:

ChannelException - if a startup error occurs or the service is already started.

See Also:

• Channel

internalStart

protected void internalStart(int svc)
                      throws ChannelException

Starts up the channel. This can be called multiple times for individual services to start The svc parameter can be the logical or value of any constants

Parameters:

svc - int value of
DEFAULT - will start all services
MBR_RX_SEQ - starts the membership receiver
MBR_TX_SEQ - starts the membership broadcaster
SND_TX_SEQ - starts the replication transmitter
SND_RX_SEQ - starts the replication receiver

Throws:

ChannelException - if a startup error occurs or the service is already started.

internalStop

protected void internalStop(int svc)
                     throws ChannelException

Shuts down the channel. This can be called multiple times for individual services to shutdown The svc parameter can be the logical or value of any constants

Parameters:

svc - int value of
DEFAULT - will shutdown all services
MBR_RX_SEQ - stops the membership receiver
MBR_TX_SEQ - stops the membership broadcaster
SND_TX_SEQ - stops the replication transmitter
SND_RX_SEQ - stops the replication receiver

Throws:

ChannelException - if a startup error occurs or the service is already started.

memberAdded

public void memberAdded(Member member)

Description copied from interface: MembershipListener

A member was added to the group

Specified by:

memberAdded in interface MembershipListener

Overrides:

memberAdded in class ChannelInterceptorBase

Parameters:

member - Member - the member that was added

memberDisappeared

public void memberDisappeared(Member member)

Description copied from interface: MembershipListener

A member was removed from the group
If the member left voluntarily, the Member.getCommand will contain the Member.SHUTDOWN_PAYLOAD data

Specified by:

memberDisappeared in interface MembershipListener

Overrides:

memberDisappeared in class ChannelInterceptorBase

Parameters:

member - Member

See Also:

• Member.SHUTDOWN_PAYLOAD

messageReceived

public void messageReceived(ChannelMessage msg)

Description copied from interface: ChannelInterceptor

The messageReceived is invoked when a message is received. ChannelMessage.getAddress() is the sender, or the reply-to address if it has been overwritten.

Specified by:

messageReceived in interface ChannelInterceptor

Specified by:

messageReceived in interface MessageListener

Overrides:

messageReceived in class ChannelInterceptorBase

Parameters:

msg - ChannelMessage

accept

public boolean accept(ChannelMessage msg)

Description copied from interface: MessageListener

Allows skipping processing of the specified message.

Specified by:

accept in interface MessageListener

Parameters:

msg - the message

Returns:

true if the message will be processed

getClusterReceiver

public ChannelReceiver getClusterReceiver()

Returns the cluster receiver.

Returns:

the cluster receiver

getClusterSender

public ChannelSender getClusterSender()

Returns the cluster sender.

Returns:

the cluster sender

getMembershipService

public MembershipService getMembershipService()

Returns the membership service.

Returns:

the membership service

setClusterReceiver

public void setClusterReceiver(ChannelReceiver clusterReceiver)

Sets the cluster receiver.

Parameters:

clusterReceiver - The new cluster receiver

setClusterSender

public void setClusterSender(ChannelSender clusterSender)

Sets the cluster sender.

Parameters:

clusterSender - The new cluster sender

setMembershipService

public void setMembershipService(MembershipService membershipService)

Sets the membership service.

Parameters:

membershipService - The new membership service

heartbeat

public void heartbeat()

Description copied from interface: ChannelInterceptor

The heartbeat() method gets invoked periodically to allow interceptors to clean up resources, time out object and perform actions that are unrelated to sending/receiving data.

Specified by:

heartbeat in interface ChannelInterceptor

Specified by:

heartbeat in interface Heartbeat

Overrides:

heartbeat in class ChannelInterceptorBase

hasMembers

public boolean hasMembers()

Description copied from interface: ChannelInterceptor

Intercepts the Channel.hasMembers() method

Specified by:

hasMembers in interface ChannelInterceptor

Overrides:

hasMembers in class ChannelInterceptorBase

Returns:

boolean - if the channel has members in its membership group

See Also:

• Channel.hasMembers()

getMembers

public Member[] getMembers()

Description copied from interface: ChannelInterceptor

Intercepts the Channel.getMembers() method

Specified by:

getMembers in interface ChannelInterceptor

Overrides:

getMembers in class ChannelInterceptorBase

Returns:

the members

See Also:

• Channel.getMembers()

getMember

public Member getMember(Member mbr)

Description copied from interface: ChannelInterceptor

Intercepts the Channel.getMember(Member) method

Specified by:

getMember in interface ChannelInterceptor

Overrides:

getMember in class ChannelInterceptorBase

Parameters:

mbr - Member

Returns:

Member - the actual member information, including stay alive

See Also:

• Channel.getMember(Member)

getLocalMember

public Member getLocalMember(boolean incAlive)

Description copied from interface: ChannelInterceptor

Intercepts the Channel.getLocalMember(boolean) method

Specified by:

getLocalMember in interface ChannelInterceptor

Overrides:

getLocalMember in class ChannelInterceptorBase

Parameters:

incAlive - boolean

Returns:

the member that represents this node

See Also:

• Channel.getLocalMember(boolean)