public McastService() 
{
             
        properties.setProperty("mcastClusterDomain", "catalina");
}

Create a membership service.

 public  void addMembershipListener(MembershipListener listener) 
{
        this.listener = listener;
}

Add a membership listener, this version only supports one listener per service, so calling this method twice will result in only the second listener being active.

 public Member findMemberByName(String name) 
{
        Member[] currentMembers = getMembers();
        for (int i = 0; i <  currentMembers.length; i++) {
            if (name.equals(currentMembers[i].toString()))
                return currentMembers[i];
        }
        return null;
}

Return the member by name

 public Cluster getCatalinaCluster() 
{
        return cluster ;
}

Return the cluster for this membership service

 public String getInfo() 
{
        return (info);
}

Return descriptive information about this implementation and the corresponding version number, in the format <description>/<version>.

 public Member getLocalMember() 
{
        localMember.setMemberAliveTime(System.currentTimeMillis()-impl.getServiceStartTime());
        return localMember;
}

Return the local member

 public String getLocalMemberName() 
{
        return localMember.toString() ;
}

Return the local member name

 public String getMcastAddr() 
{
        return properties.getProperty("mcastAddress");
}

 public String getMcastBindAddress() 
{
        return properties.getProperty("mcastBindAddress");
}

 public String getMcastClusterDomain() 
{
        return properties.getProperty("mcastClusterDomain");
}

 public long getMcastDropTime() 
{
        String p = properties.getProperty("memberDropTime");
        return new Long(p).longValue();
}

 public long getMcastFrequency() 
{
        String p = properties.getProperty("msgFrequency");
        return new Long(p).longValue();
}

 public int getMcastPort() 
{
        String p = properties.getProperty("mcastPort");
        return new Integer(p).intValue();
}

 public int getMcastSoTimeout() 
{
        return mcastSoTimeout;
}

 public int getMcastTTL() 
{
        return mcastTTL;
}

 public Member[] getMembers() 
{
        if ( impl == null || impl.membership == null ) return null;
        return impl.membership.getMembers();
}

Return all the members

 public String[] getMembersByName() 
{
        Member[] currentMembers = getMembers();
        String [] membernames ;
        if(currentMembers != null) {
            membernames = new String[currentMembers.length];
            for (int i = 0; i <  currentMembers.length; i++) {
                membernames[i] = currentMembers[i].toString() ;
            }
        } else
            membernames = new String[0] ;
        return membernames ;
}

Return all the members by name

 public ObjectName getObjectName() 
{
        return objectName;
}

 public Properties getProperties() 
{
        return properties;
}

Return the properties, see setProperties

 protected  void hasProperty(Properties properties,
    String name) 
{
        if ( properties.getProperty(name)==null) throw new IllegalArgumentException("Required property \""+name+"\" is missing.");
}

Check if a required property is available.

 protected  void initMBeans() throws Exception 
{
      if(registry == null) {
        registry = Registry.getRegistry(null, null);
        registry.loadMetadata(this.getClass().getResourceAsStream(
            "mbeans-descriptors.xml"));
      }
}

register mbean descriptor for package mcast

 public static  void main(String[] args) throws Exception 
{
		if(log.isInfoEnabled())
            log.info("Usage McastService hostname tcpport");
        McastService service = new McastService();
        java.util.Properties p = new java.util.Properties();
        p.setProperty("mcastPort","5555");
        p.setProperty("mcastAddress","224.10.10.10");
        p.setProperty("mcastClusterDomain","catalina");
        p.setProperty("bindAddress","localhost");
        p.setProperty("memberDropTime","3000");
        p.setProperty("msgFrequency","500");
        p.setProperty("tcpListenPort",args[1]);
        p.setProperty("tcpListenHost",args[0]);
        service.setProperties(p);
        service.start();
        Thread.sleep(60*1000*60);
}

Simple test program

 public  void memberAdded(Member member) 
{
        if ( listener!=null ) listener.memberAdded(member);
}

 public  void memberDisappeared(Member member) 
{
        if ( listener!=null ) listener.memberDisappeared(member);
}

Callback from the impl when a new member has been received

 protected  void registerMBean() 
{
        if (cluster != null) {
            ObjectName clusterName = cluster.getObjectName();
            try {
                MBeanServer mserver = cluster.getMBeanServer();
                initMBeans();
                Container container = cluster.getContainer();
                String name = clusterName.getDomain() + ":type=ClusterMembership";
                if (container instanceof StandardHost) {
                    name += ",host=" + clusterName.getKeyProperty("host");
                }
                ObjectName mcastName = new ObjectName(name);
                if (mserver.isRegistered(mcastName)) {
                    if (log.isWarnEnabled())
                        log.warn(sm.getString(
                                "cluster.mbean.register.allready", mcastName));
                    return;
                }
                setObjectName(mcastName);
                mserver.registerMBean(cluster.getManagedBean(this),
                        getObjectName());
                if (log.isInfoEnabled())
                    log.info("membership mbean registered (" + mcastName + ")");
            } catch (Exception e) {
                log.warn("membership mbean creation failed (" + clusterName + ")" ,e);
            }
        }
}

register MBeans for Membership

 public  void removeMembershipListener() 
{
        listener = null;
}

Remove the membership listener

 public  void setCatalinaCluster(SimpleTcpCluster cluster) 
{
        this.cluster = cluster;
}

 public  void setLocalMemberProperties(String listenHost,
    int listenPort) 
{
        properties.setProperty("tcpListenHost",listenHost);
        properties.setProperty("tcpListenPort",String.valueOf(listenPort));
}

Sets the local member properties for broadcasting

 public  void setMcastAddr(String addr) 
{
        properties.setProperty("mcastAddress", addr);
}

 public  void setMcastBindAddress(String bindaddr) 
{
        properties.setProperty("mcastBindAddress", bindaddr);
}

 public  void setMcastClusterDomain(String clusterDomain) 
{
        properties.setProperty("mcastClusterDomain", clusterDomain);
}

 public  void setMcastDropTime(long time) 
{
        properties.setProperty("memberDropTime", String.valueOf(time));
}

 public  void setMcastFrequency(long time) 
{
        properties.setProperty("msgFrequency", String.valueOf(time));
}

 public  void setMcastPort(int port) 
{
        properties.setProperty("mcastPort", String.valueOf(port));
}

 public  void setMcastSoTimeout(int mcastSoTimeout) 
{
        this.mcastSoTimeout = mcastSoTimeout;
        properties.setProperty("mcastSoTimeout", String.valueOf(mcastSoTimeout));
}

 public  void setMcastTTL(int mcastTTL) 
{
        this.mcastTTL = mcastTTL;
        properties.setProperty("mcastTTL", String.valueOf(mcastTTL));
}

 public  void setObjectName(ObjectName name) 
{
        objectName = name;
}

Transmitter ObjectName

 public  void setProperties(Properties properties) 
{
        hasProperty(properties,"mcastPort");
        hasProperty(properties,"mcastAddress");
        hasProperty(properties,"mcastClusterDomain");
        hasProperty(properties,"memberDropTime");
        hasProperty(properties,"msgFrequency");
        hasProperty(properties,"tcpListenPort");
        hasProperty(properties,"tcpListenHost");
        this.properties = properties;
}

 public  void start() throws Exception 
{
        start(1);
        start(2);
        registerMBean();
}

Start broadcasting and listening to membership pings

 public  void start(int level) throws Exception 
{
        if ( impl != null ) {
            impl.start(level);
            return;
        }
        String host = getProperties().getProperty("tcpListenHost");
        String domain = getProperties().getProperty("mcastClusterDomain");
        int port = Integer.parseInt(getProperties().getProperty("tcpListenPort"));
        String name = "tcp://"+host+":"+port;
        if ( localMember == null ) {
            localMember = new McastMember(name, domain, host, port, 100);
        } else {
            localMember.setName(name);
            localMember.setDomain(domain);
            localMember.setHost(host);
            localMember.setPort(port);
            localMember.setMemberAliveTime(100);
        }
        java.net.InetAddress bind = null;
        if ( properties.getProperty("mcastBindAddress")!= null ) {
            bind = java.net.InetAddress.getByName(properties.getProperty("mcastBindAddress"));
        }
        int ttl = -1;
        int soTimeout = -1;
        if ( properties.getProperty("mcastTTL") != null ) {
            try {
                ttl = Integer.parseInt(properties.getProperty("mcastTTL"));
            } catch ( Exception x ) {
                log.error("Unable to parse mcastTTL="+properties.getProperty("mcastTTL"),x);
            }
        }
        if ( properties.getProperty("mcastSoTimeout") != null ) {
            try {
                soTimeout = Integer.parseInt(properties.getProperty("mcastSoTimeout"));
            } catch ( Exception x ) {
                log.error("Unable to parse mcastSoTimeout="+properties.getProperty("mcastSoTimeout"),x);
            }
        }
        impl = new McastServiceImpl((McastMember)localMember,Long.parseLong(properties.getProperty("msgFrequency")),
                                    Long.parseLong(properties.getProperty("memberDropTime")),
                                    Integer.parseInt(properties.getProperty("mcastPort")),
                                    bind,
                                    java.net.InetAddress.getByName(properties.getProperty("mcastAddress")),
                                    ttl,
                                    soTimeout,
                                    this);
        impl.start(level);
		long memberwait = (Long.parseLong(properties.getProperty("msgFrequency"))*4);
        if(log.isInfoEnabled())
            log.info("Sleeping for "+memberwait+" secs to establish cluster membership");
        Thread.sleep(memberwait);
}

 public  void stop() 
{
        try  {
            if ( impl != null) impl.stop();
        } catch ( Exception x)  {
            log.error("Unable to stop the mcast service.",x);
        }
        impl = null;
        unregisterMBean();
}

Stop broadcasting and listening to membership pings

 protected  void unregisterMBean() 
{
        if (cluster != null && getObjectName() != null) {
            try {
                MBeanServer mserver = cluster.getMBeanServer();
                mserver.unregisterMBean(getObjectName());
            } catch (Exception e) {
                log.error(e);
            }
        }
}

unregister MBeans for Membership