/* | |
* Copyright 1999-2011 Alibaba Group. | |
* | |
* Licensed under the Apache License, Version 2.0 (the "License"); | |
* you may not use this file except in compliance with the License. | |
* You may obtain a copy of the License at | |
* | |
* http://www.apache.org/licenses/LICENSE-2.0 | |
* | |
* Unless required by applicable law or agreed to in writing, software | |
* distributed under the License is distributed on an "AS IS" BASIS, | |
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
* See the License for the specific language governing permissions and | |
* limitations under the License. | |
*/ | |
package com.alibaba.dubbo.remoting.p2p.support; | |
import java.io.IOException; | |
import java.net.DatagramPacket; | |
import java.net.InetAddress; | |
import java.net.InetSocketAddress; | |
import java.net.MulticastSocket; | |
import com.alibaba.dubbo.common.URL; | |
import com.alibaba.dubbo.common.utils.StringUtils; | |
import com.alibaba.dubbo.remoting.ChannelHandler; | |
import com.alibaba.dubbo.remoting.RemotingException; | |
import com.alibaba.dubbo.remoting.p2p.Peer; | |
/** | |
* MulticastGroup | |
* | |
* @author william.liangf | |
*/ | |
public class MulticastGroup extends AbstractGroup { | |
private static final String JOIN = "join"; | |
private static final String LEAVE = "leave"; | |
private InetAddress mutilcastAddress; | |
private MulticastSocket mutilcastSocket; | |
public MulticastGroup(URL url) { | |
super(url); | |
if (! isMulticastAddress(url.getHost())) { | |
throw new IllegalArgumentException("Invalid multicast address " + url.getHost() + ", scope: 224.0.0.0 - 239.255.255.255"); | |
} | |
try { | |
mutilcastAddress = InetAddress.getByName(url.getHost()); | |
mutilcastSocket = new MulticastSocket(url.getPort()); | |
mutilcastSocket.setLoopbackMode(false); | |
mutilcastSocket.joinGroup(mutilcastAddress); | |
Thread thread = new Thread(new Runnable() { | |
public void run() { | |
byte[] buf = new byte[1024]; | |
DatagramPacket recv = new DatagramPacket(buf, buf.length); | |
while (true) { | |
try { | |
mutilcastSocket.receive(recv); | |
MulticastGroup.this.receive(new String(recv.getData()).trim(), (InetSocketAddress) recv.getSocketAddress()); | |
} catch (Exception e) { | |
logger.error(e.getMessage(), e); | |
} | |
} | |
} | |
}, "MulticastGroupReceiver"); | |
thread.setDaemon(true); | |
thread.start(); | |
} catch (IOException e) { | |
throw new IllegalStateException(e.getMessage(), e); | |
} | |
} | |
private static boolean isMulticastAddress(String ip) { | |
int i = ip.indexOf('.'); | |
if (i > 0) { | |
String prefix = ip.substring(0, i); | |
if (StringUtils.isInteger(prefix)) { | |
int p = Integer.parseInt(prefix); | |
return p >= 224 && p <= 239; | |
} | |
} | |
return false; | |
} | |
private void send(String msg) throws RemotingException { | |
DatagramPacket hi = new DatagramPacket(msg.getBytes(), msg.length(), mutilcastAddress, mutilcastSocket.getLocalPort()); | |
try { | |
mutilcastSocket.send(hi); | |
} catch (IOException e) { | |
throw new IllegalStateException(e.getMessage(), e); | |
} | |
} | |
private void receive(String msg, InetSocketAddress remoteAddress) throws RemotingException { | |
if (msg.startsWith(JOIN)) { | |
String url = msg.substring(JOIN.length()).trim(); | |
connect(URL.valueOf(url)); | |
} else if (msg.startsWith(LEAVE)) { | |
String url = msg.substring(LEAVE.length()).trim(); | |
disconnect(URL.valueOf(url)); | |
} | |
} | |
@Override | |
public Peer join(URL url, ChannelHandler handler) throws RemotingException { | |
Peer peer = super.join(url, handler); | |
send(JOIN + " " + url.toFullString()); | |
return peer; | |
} | |
@Override | |
public void leave(URL url) throws RemotingException { | |
super.leave(url); | |
send(LEAVE + " " + url.toFullString()); | |
} | |
} |