org.apache.catalina.tribes.group
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.

Author:

Filip Hanik

optionFlag

protected int optionFlag

ChannelCoordinator

public ChannelCoordinator()

ChannelCoordinator

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

getOptionFlag

public int getOptionFlag()

Description copied from interface: ChannelInterceptor

An interceptor can react to a message based on a set bit on the message options.
When a message is sent, the options can be retrieved from ChannelMessage.getOptions() and if the bit is set, this interceptor will react to it.
A simple evaluation if an interceptor should react to the message would be:
boolean react = (getOptionFlag() == (getOptionFlag() & ChannelMessage.getOptions()));
The default option is 0, meaning there is no way for the application to trigger the interceptor. The interceptor itself will decide.

Specified by:

getOptionFlag in interface ChannelInterceptor

Overrides:

getOptionFlag in class ChannelInterceptorBase

Returns:

int

See Also:

ChannelMessage.getOptions()

setOptionFlag

public void setOptionFlag(int flag)

Description copied from interface: ChannelInterceptor

Sets the option flag

Specified by:

setOptionFlag in interface ChannelInterceptor

Overrides:

setOptionFlag in class ChannelInterceptorBase

Parameters:

flag - int

See Also:

ChannelInterceptor.getOptionFlag()

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 - InterceptorPayload - the payload, carrying an error handler and future useful data, can be null

Throws:

ChannelException

See Also:

ErrorHandler, InterceptorPayload

start

public void start(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

Specified by:

start in interface ChannelInterceptor

Overrides:

start in class ChannelInterceptorBase

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.

See Also:

Channel

stop

public void stop(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

Specified by:

stop in interface ChannelInterceptor

Overrides:

stop in class ChannelInterceptorBase

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.

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 - 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.

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

getClusterReceiver

public ChannelReceiver getClusterReceiver()

getClusterSender

public ChannelSender getClusterSender()

getMembershipService

public MembershipService getMembershipService()

setClusterReceiver

public void setClusterReceiver(ChannelReceiver clusterReceiver)

setClusterSender

public void setClusterSender(ChannelSender clusterSender)

setMembershipService

public void setMembershipService(MembershipService membershipService)

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()

has members

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()

Get all current cluster members

Specified by:

getMembers in interface ChannelInterceptor

Overrides:

getMembers in class ChannelInterceptorBase

Returns:

all members or empty array

See Also:

Channel.getMembers()

getMember

public Member getMember(Member mbr)

Description copied from interface: ChannelInterceptor

Intercepts the code>Channel.getMember(Member) method

Specified by:

getMember in interface ChannelInterceptor

Overrides:

getMember in class ChannelInterceptorBase

Parameters:

mbr - Member

Returns:

Member

See Also:

Channel.getMember(Member)

getLocalMember

public Member getLocalMember(boolean incAlive)

Return the member that represents this node.

Specified by:

getLocalMember in interface ChannelInterceptor

Overrides:

getLocalMember in class ChannelInterceptorBase

Parameters:

incAlive - boolean

Returns:

Member

See Also:

Channel.getLocalMember(boolean)