mcastservice.java

业界著名的tomcat服务器的最新6.0的源代码。

    /**
     * Check if a required property is available.
     * @param properties The set of properties
     * @param name The property to check for
     */
    protected void hasProperty(Properties properties, String name){
        if ( properties.getProperty(name)==null) throw new IllegalArgumentException("McastService:Required property \""+name+"\" is missing.");
    }

    /**
     * Start broadcasting and listening to membership pings
     * @throws java.lang.Exception if a IO error occurs
     */
    public void start() throws java.lang.Exception {
        start(MembershipService.MBR_RX);
        start(MembershipService.MBR_TX);
    }
    
    public void start(int level) throws java.lang.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);
        
        impl.start(level);
		

    }

 
    /**
     * Stop broadcasting and listening to membership pings
     */
    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);
        }
    }


    /**
     * Return all the members by name
     */
    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 the member by name
     */
    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;
    }

    /**
     * has members?
     */
    public boolean hasMembers() {
       if ( impl == null || impl.membership == null ) return false;
       return impl.membership.hasMembers();
    }
    
    public Member getMember(Member mbr) {
        if ( impl == null || impl.membership == null ) return null;
        return impl.membership.getMember(mbr);
    }

    /**
     * Return all the members
     */
    public Member[] getMembers() {
        if ( impl == null || impl.membership == null ) return null;
        return impl.membership.getMembers();
    }
    /**
     * 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.
     * @param listener The listener
     */
    public void setMembershipListener(MembershipListener listener) {
        this.listener = listener;
    }
    /**
     * Remove the membership listener
     */
    public void removeMembershipListener(){
        listener = null;
    }

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

    /**
     * Callback from the impl when a new member has been received
     * @param member The member
     */
    public void memberDisappeared(Member member)
    {
        if ( listener!=null ) listener.memberDisappeared(member);
    }

    /**
     * @deprecated use getSoTimeout
     * @return int
     */
    public int getMcastSoTimeout() {
        return getSoTimeout();
    }
    
    public int getSoTimeout() {
        return mcastSoTimeout;
    }
    
    /**
     * @deprecated use setSoTimeout
     * @param mcastSoTimeout int
     */
    public void setMcastSoTimeout(int mcastSoTimeout) {
        setSoTimeout(mcastSoTimeout);
    }
    
    public void setSoTimeout(int mcastSoTimeout) {
        this.mcastSoTimeout = mcastSoTimeout;
        properties.setProperty("mcastSoTimeout", String.valueOf(mcastSoTimeout));
    }
    
    /**
     * @deprecated use getTtl
     * @return int
     */
    public int getMcastTTL() {
        return getTtl();
    }
    
    public int getTtl() {
        return mcastTTL;
    }

    public byte[] getPayload() {
        return payload;
    }
    
    public byte[] getDomain() {
        return domain;
    }
    
    /**
     * @deprecated use setTtl
     * @param mcastTTL int
     */
    public void setMcastTTL(int mcastTTL) {
        setTtl(mcastTTL);
    }

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

    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 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);
            }
        }
    }

    /**
     * Simple test program
     * @param args Command-line arguments
     * @throws Exception If an error occurs
     */
    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);
    }
}