org.apache.catalina.cluster.mcast
Class McastMembership

java.lang.Object
  org.apache.catalina.cluster.mcast.McastMembership

public class McastMembership

extends java.lang.Object

A membership implementation using simple multicast. This is the representation of a multicast membership. This class is responsible for maintaining a list of active cluster nodes in the cluster. If a node fails to send out a heartbeat, the node will be dismissed.

Version:

$Id: McastMembership.java 939539 2010-04-30 01:31:33Z kkolinko $

Author:

Filip Hanik, Peter Rossbach

Nested Class Summary

protected static class

McastMembership.MbrEntry Inner class that represents a member entry

Field Summary

protected static McastMember[]	EMPTY_MEMBERS
protected java.util.Map	map A map of all the members in the cluster.
protected org.apache.catalina.cluster.mcast.McastMembership.MemberComparator	memberComparator sort members by alive time
protected McastMember[]	members A list of all the members in the cluster.
protected java.lang.String	name The name of this membership, has to be the same as the name for the local member

Constructor Summary

McastMembership(java.lang.String name)
Constructs a new membership

Method Summary

protected void	addMcastMember(McastMember member) Add a member to this component and sort array with memberComparator
McastMember[]	expire(long maxtime) Runs a refresh cycle and returns a list of members that has expired.
protected McastMembership.MbrEntry[]	getMemberEntries() get a copy from all member entries
McastMember[]	getMembers() Returning a list of all the members in the membership We not need a copy: add and remove generate new arrays.
boolean	hasMembers() Returning that service has members or not
boolean	memberAlive(McastMember member) Notify the membership that this member has announced itself.
protected void	removeMcastMember(McastMember member) Remove a member from this component.
void	reset() Reset the membership and start over fresh.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_MEMBERS

protected static final McastMember[] EMPTY_MEMBERS

name

protected java.lang.String name

The name of this membership, has to be the same as the name for the local member

map

protected java.util.Map map

A map of all the members in the cluster.

members

protected McastMember[] members

A list of all the members in the cluster.

memberComparator

protected org.apache.catalina.cluster.mcast.McastMembership.MemberComparator memberComparator

sort members by alive time

Constructor Detail

McastMembership

public McastMembership(java.lang.String name)

Constructs a new membership

Parameters:

name - - has to be the name of the local member. Used to filter the local member from the cluster membership

Method Detail

reset

public void reset()

Reset the membership and start over fresh. Ie, delete all the members and wait for them to ping again and join this membership

memberAlive

public boolean memberAlive(McastMember member)

Notify the membership that this member has announced itself.

Parameters:

member - - the member that just pinged us

Returns:

- true if this member is new to the cluster, false otherwise.

addMcastMember

protected void addMcastMember(McastMember member)

Add a member to this component and sort array with memberComparator

Parameters:

member - The member to add

removeMcastMember

protected void removeMcastMember(McastMember member)

Remove a member from this component.

Parameters:

member - The member to remove

expire

public McastMember[] expire(long maxtime)

Runs a refresh cycle and returns a list of members that has expired. This also removes the members from the membership, in such a way that getMembers() = getMembers() - expire()

Parameters:

maxtime - - the max time a member can remain unannounced before it is considered dead.

Returns:

the list of expired members

hasMembers

public boolean hasMembers()

Returning that service has members or not

getMembers

public McastMember[] getMembers()

Returning a list of all the members in the membership We not need a copy: add and remove generate new arrays.

getMemberEntries

protected McastMembership.MbrEntry[] getMemberEntries()

get a copy from all member entries