public McastService() 
{
             
        //default values
        properties.setProperty("mcastPort","45564");
        properties.setProperty("mcastAddress","228.0.0.4");
        properties.setProperty("memberDropTime","3000");
        properties.setProperty("mcastFrequency","500");
}

Create a membership service.

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

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

 public byte[] getDomain() 
{
        return domain;
}

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

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

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

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

 public Member getLocalMember(boolean alive) 
{
        if ( alive && localMember != null && impl != null) 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 getAddress();
}

 public String getMcastBindAddress() 
{
        return getBind();
}

 public long getMcastDropTime() 
{
        return getDropTime();
}

 public long getMcastFrequency() 
{
        return getFrequency();
}

 public int getMcastPort() 
{
        return getPort();
}

 public int getMcastSoTimeout() 
{
        return getSoTimeout();
}

 public int getMcastTTL() 
{
        return getTtl();
}

 public Member getMember(Member mbr) 
{
        if ( impl == null || impl.membership == null ) return null;
        return impl.membership.getMember(mbr);
}

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

 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 byte[] getPayload() 
{
        return payload;
}

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

 public Properties getProperties() 
{
        return properties;
}

Return the properties, see setProperties

 public int getSoTimeout() 
{
        return mcastSoTimeout;
}

 public int getTtl() 
{
        return mcastTTL;
}

 public boolean hasMembers() 
{
       if ( impl == null || impl.membership == null ) return false;
       return impl.membership.hasMembers();
}

has members?

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

Check if a required property is available.

 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("mcastFrequency","500");
        p.setProperty("tcpListenPort","4000");
        p.setProperty("tcpListenHost","127.0.0.1");
        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

 public  void removeMembershipListener() 
{
        listener = null;
}

Remove the membership listener

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

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

 public  void setDomain(byte[] domain) 
{
        this.domain = domain;
        if ( localMember != null ) {
            localMember.setDomain(domain);
            localMember.getData(true,true);
            try {
                if (impl != null) impl.send(false);
            }catch ( Exception x ) {
                log.error("Unable to send domain update.",x);
            }
        }
}

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

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

 public  void setLocalMemberProperties(String listenHost,
    int listenPort) 
{
        properties.setProperty("tcpListenHost",listenHost);
        properties.setProperty("tcpListenPort",String.valueOf(listenPort));
        try {
            if (localMember != null) {
                localMember.setHostname(listenHost);
                localMember.setPort(listenPort);
            } else {
                localMember = new MemberImpl(listenHost, listenPort, 0);
                localMember.setUniqueId(UUIDGenerator.randomUUID(true));
                localMember.setPayload(getPayload());
                localMember.setDomain(getDomain());
            }
            localMember.getData(true, true);
        }catch ( IOException x ) {
            throw new IllegalArgumentException(x);
        }
}

Sets the local member properties for broadcasting

 public  void setMcastAddr(String addr) 
{
        setAddress(addr);
}

 public  void setMcastBindAddress(String bindaddr) 
{
        setBind(bindaddr);
}

 public  void setMcastDropTime(long time) 
{
        setDropTime(time);
}

 public  void setMcastFrequency(long time) 
{
        setFrequency(time);
}

 public  void setMcastPort(int port) 
{
        setPort(port);
}

 public  void setMcastSoTimeout(int mcastSoTimeout) 
{
        setSoTimeout(mcastSoTimeout);
}

 public  void setMcastTTL(int mcastTTL) 
{
        setTtl(mcastTTL);
}

 public  void setMembershipListener(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  void setPayload(byte[] payload) 
{
        this.payload = payload;
        if ( localMember != null ) {
            localMember.setPayload(payload);
            localMember.getData(true,true);
            try {
                if (impl != null) impl.send(false);
            }catch ( Exception x ) {
                log.error("Unable to send payload update.",x);
            }
        }
}

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

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

 public  void setRecoveryCounter(int recoveryCounter) 
{
        properties.setProperty("recoveryCounter", String.valueOf(recoveryCounter));
}

 public  void setRecoveryEnabled(boolean recoveryEnabled) 
{
        properties.setProperty("recoveryEnabled", String.valueOf(recoveryEnabled));
}

 public  void setRecoverySleepTime(long recoverySleepTime) 
{
        properties.setProperty("recoverySleepTime", String.valueOf(recoverySleepTime));
}

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

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

 public  void start() throws Exception 
{
        start(MembershipService.MBR_RX);
        start(MembershipService.MBR_TX);
}

Start broadcasting and listening to membership pings

 public  void start(int level) throws Exception 
{
        hasProperty(properties,"mcastPort");
        hasProperty(properties,"mcastAddress");
        hasProperty(properties,"memberDropTime");
        hasProperty(properties,"mcastFrequency");
        hasProperty(properties,"tcpListenPort");
        hasProperty(properties,"tcpListenHost");
        if ( impl != null ) {
            impl.start(level);
            return;
        }
        String host = getProperties().getProperty("tcpListenHost");
        int port = Integer.parseInt(getProperties().getProperty("tcpListenPort"));
        if ( localMember == null ) {
            localMember = new MemberImpl(host, port, 100);
            localMember.setUniqueId(UUIDGenerator.randomUUID(true));
        } else {
            localMember.setHostname(host);
            localMember.setPort(port);
            localMember.setMemberAliveTime(100);
        }
        if ( this.payload != null ) localMember.setPayload(payload);
        if ( this.domain != null ) localMember.setDomain(domain);
        localMember.setServiceStartTime(System.currentTimeMillis());
        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((MemberImpl)localMember,Long.parseLong(properties.getProperty("mcastFrequency")),
                                    Long.parseLong(properties.getProperty("memberDropTime")),
                                    Integer.parseInt(properties.getProperty("mcastPort")),
                                    bind,
                                    java.net.InetAddress.getByName(properties.getProperty("mcastAddress")),
                                    ttl,
                                    soTimeout,
                                    this);
        String value = properties.getProperty("recoveryEnabled","true");
        boolean recEnabled = Boolean.valueOf(value).booleanValue() ;
        impl.setRecoveryEnabled(recEnabled);        
        int recCnt = Integer.parseInt(properties.getProperty("recoveryCounter","10"));
        impl.setRecoveryCounter(recCnt);
        long recSlpTime = Long.parseLong(properties.getProperty("recoverySleepTime","5000"));
        impl.setRecoverySleepTime(recSlpTime);
        impl.start(level);
}

 public  void stop(int svc) 
{
        try  {
            if ( impl != null && impl.stop(svc) ) impl = null;
        } catch ( Exception x)  {
            log.error("Unable to stop the mcast service, level:"+svc+".",x);
        }
}

Stop broadcasting and listening to membership pings