Package org.apache.catalina.tribes.group.interceptors

Class SimpleCoordinator

java.lang.Object

org.apache.catalina.tribes.group.ChannelInterceptorBase

org.apache.catalina.tribes.group.interceptors.SimpleCoordinator

All Implemented Interfaces:

ChannelInterceptor, Heartbeat, MembershipListener

public class SimpleCoordinator
extends ChannelInterceptorBase

A dinky coordinator, just uses a sorted version of the member array.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.catalina.tribes.ChannelInterceptor

ChannelInterceptor.InterceptorEvent

Field Summary

Fields inherited from class org.apache.catalina.tribes.group.ChannelInterceptorBase

optionFlag

Constructor Summary

Constructors

Constructor	Description
SimpleCoordinator()	Creates a new SimpleCoordinator instance.

Method Summary

Modifier and Type	Method	Description
Member	getCoordinator()	Returns the current coordinator member (first member in the sorted view).
Member[]	getView()	Returns the current sorted view of cluster members.
boolean	isCoordinator()	Returns whether this member is the current coordinator.
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	start(int svc)	Starts up the channel.
void	stop(int svc)	Shuts down the channel.
protected void	viewChange(Member[] view)	Override to receive view changes.

Methods inherited from class org.apache.catalina.tribes.group.ChannelInterceptorBase

fireInterceptorEvent, getChannel, getLocalMember, getMember, getMembers, getNext, getOptionFlag, getPrevious, hasMembers, heartbeat, messageReceived, okToProcess, sendMessage, setChannel, setNext, setOptionFlag, setPrevious

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleCoordinator

public SimpleCoordinator()

Creates a new SimpleCoordinator instance.

Method Detail

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

viewChange

protected void viewChange(Member[] view)

Override to receive view changes.

Parameters:

view - The members array

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

getView

public Member[] getView()

Returns the current sorted view of cluster members.

Returns:

the current member view, or null if not yet established

getCoordinator

public Member getCoordinator()

Returns the current coordinator member (first member in the sorted view).

Returns:

the coordinator member, or null if no view is established

isCoordinator

public boolean isCoordinator()

Returns whether this member is the current coordinator.

Returns:

true if this member is the coordinator