/* | |
* 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.registry.multicast; | |
import java.io.IOException; | |
import java.net.DatagramPacket; | |
import java.net.InetAddress; | |
import java.net.InetSocketAddress; | |
import java.net.MulticastSocket; | |
import java.net.Socket; | |
import java.util.ArrayList; | |
import java.util.Arrays; | |
import java.util.HashSet; | |
import java.util.List; | |
import java.util.Map; | |
import java.util.Set; | |
import java.util.concurrent.ConcurrentHashMap; | |
import java.util.concurrent.ConcurrentMap; | |
import java.util.concurrent.Executors; | |
import java.util.concurrent.ScheduledExecutorService; | |
import java.util.concurrent.ScheduledFuture; | |
import java.util.concurrent.TimeUnit; | |
import com.alibaba.dubbo.common.Constants; | |
import com.alibaba.dubbo.common.URL; | |
import com.alibaba.dubbo.common.logger.Logger; | |
import com.alibaba.dubbo.common.logger.LoggerFactory; | |
import com.alibaba.dubbo.common.utils.ConcurrentHashSet; | |
import com.alibaba.dubbo.common.utils.NamedThreadFactory; | |
import com.alibaba.dubbo.common.utils.NetUtils; | |
import com.alibaba.dubbo.common.utils.StringUtils; | |
import com.alibaba.dubbo.common.utils.UrlUtils; | |
import com.alibaba.dubbo.registry.NotifyListener; | |
import com.alibaba.dubbo.registry.support.FailbackRegistry; | |
/** | |
* MulticastRegistry | |
* | |
* @author william.liangf | |
*/ | |
public class MulticastRegistry extends FailbackRegistry { | |
// 日志输出 | |
private static final Logger logger = LoggerFactory.getLogger(MulticastRegistry.class); | |
private static final int DEFAULT_MULTICAST_PORT = 1234; | |
private final InetAddress mutilcastAddress; | |
private final MulticastSocket mutilcastSocket; | |
private final ConcurrentMap<String, Set<String>> notified = new ConcurrentHashMap<String, Set<String>>(); | |
private final ScheduledExecutorService cleanExecutor = Executors.newScheduledThreadPool(1, new NamedThreadFactory("DubboMulticastRegistryCleanTimer", true)); | |
private final ScheduledFuture<?> cleanFuture; | |
private final int cleanPeriod; | |
private volatile boolean admin = false; | |
public MulticastRegistry(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() == 0 ? DEFAULT_MULTICAST_PORT : url.getPort()); | |
mutilcastSocket.setLoopbackMode(false); | |
mutilcastSocket.joinGroup(mutilcastAddress); | |
Thread thread = new Thread(new Runnable() { | |
public void run() { | |
byte[] buf = new byte[2048]; | |
DatagramPacket recv = new DatagramPacket(buf, buf.length); | |
while (! mutilcastSocket.isClosed()) { | |
try { | |
mutilcastSocket.receive(recv); | |
String msg = new String(recv.getData()).trim(); | |
int i = msg.indexOf('\n'); | |
if (i > 0) { | |
msg = msg.substring(0, i).trim(); | |
} | |
MulticastRegistry.this.receive(msg, (InetSocketAddress) recv.getSocketAddress()); | |
Arrays.fill(buf, (byte)0); | |
} catch (Throwable e) { | |
if (! mutilcastSocket.isClosed()) { | |
logger.error(e.getMessage(), e); | |
} | |
} | |
} | |
} | |
}, "DubboMulticastRegistryReceiver"); | |
thread.setDaemon(true); | |
thread.start(); | |
} catch (IOException e) { | |
throw new IllegalStateException(e.getMessage(), e); | |
} | |
this.cleanPeriod = url.getParameter(Constants.SESSION_TIMEOUT_KEY, Constants.DEFAULT_SESSION_TIMEOUT); | |
if (url.getParameter("clean", true)) { | |
this.cleanFuture = cleanExecutor.scheduleWithFixedDelay(new Runnable() { | |
public void run() { | |
try { | |
clean(); // 清除过期者 | |
} catch (Throwable t) { // 防御性容错 | |
logger.error("Unexpected exception occur at clean expired provider, cause: " + t.getMessage(), t); | |
} | |
} | |
}, cleanPeriod, cleanPeriod, TimeUnit.MILLISECONDS); | |
} else { | |
this.cleanFuture = null; | |
} | |
} | |
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 clean() { | |
if (admin) { | |
for (Set<String> providers : new HashSet<Set<String>>(notified.values())) { | |
for (String provider : new HashSet<String>(providers)) { | |
URL url = URL.valueOf(provider); | |
if (isExpired(url)) { | |
if (logger.isWarnEnabled()) { | |
logger.warn("Clean expired provider " + url); | |
} | |
doUnregister(url); | |
} | |
} | |
} | |
} | |
} | |
private boolean isExpired(URL url) { | |
if (Constants.SUBSCRIBE_PROTOCOL.equals(url.getProtocol()) | |
|| Constants.ROUTE_PROTOCOL.equals(url.getProtocol()) | |
|| Constants.OVERRIDE_PROTOCOL.equals(url.getProtocol())) { | |
return false; | |
} | |
Socket socket = null; | |
try { | |
socket = new Socket(url.getHost(), url.getPort()); | |
} catch (Throwable e) { | |
try { | |
Thread.sleep(100); | |
} catch (Throwable e2) { | |
} | |
Socket socket2 = null; | |
try { | |
socket2 = new Socket(url.getHost(), url.getPort()); | |
} catch (Throwable e2) { | |
return true; | |
} finally { | |
if (socket2 != null) { | |
try { | |
socket2.close(); | |
} catch (Throwable e2) { | |
} | |
} | |
} | |
} finally { | |
if (socket != null) { | |
try { | |
socket.close(); | |
} catch (Throwable e) { | |
} | |
} | |
} | |
return false; | |
} | |
private void receive(String msg, InetSocketAddress remoteAddress) { | |
if (logger.isInfoEnabled()) { | |
logger.info("Receive multicast message: " + msg + " from " + remoteAddress); | |
} | |
if (msg.startsWith(Constants.REGISTER)) { | |
URL url = URL.valueOf(msg.substring(Constants.REGISTER.length()).trim()); | |
registered(url); | |
} else if (msg.startsWith(Constants.UNREGISTER)) { | |
URL url = URL.valueOf(msg.substring(Constants.UNREGISTER.length()).trim()); | |
unregistered(url); | |
} else if (msg.startsWith(Constants.SUBSCRIBE)) { | |
URL url = URL.valueOf(msg.substring(Constants.SUBSCRIBE.length()).trim()); | |
List<URL> urls = lookup(url); | |
if (urls != null && urls.size() > 0) { | |
for (URL u : urls) { | |
String host = remoteAddress != null && remoteAddress.getAddress() != null | |
? remoteAddress.getAddress().getHostAddress() : url.getIp(); | |
if (url.getParameter("unicast", true) // 消费者的机器是否只有一个进程 | |
&& ! NetUtils.getLocalHost().equals(host)) { // 同机器多进程不能用unicast单播信息,否则只会有一个进程收到信息 | |
unicast(Constants.REGISTER + " " + u.toFullString(), host); | |
} else { | |
broadcast(Constants.REGISTER + " " + u.toFullString()); | |
} | |
} | |
} | |
}/* else if (msg.startsWith(UNSUBSCRIBE)) { | |
}*/ | |
} | |
private void broadcast(String msg) { | |
if (logger.isInfoEnabled()) { | |
logger.info("Send broadcast message: " + msg + " to " + mutilcastAddress + ":" + mutilcastSocket.getLocalPort()); | |
} | |
try { | |
byte[] data = (msg + "\n").getBytes(); | |
DatagramPacket hi = new DatagramPacket(data, data.length, mutilcastAddress, mutilcastSocket.getLocalPort()); | |
mutilcastSocket.send(hi); | |
} catch (Exception e) { | |
throw new IllegalStateException(e.getMessage(), e); | |
} | |
} | |
private void unicast(String msg, String host) { | |
if (logger.isInfoEnabled()) { | |
logger.info("Send unicast message: " + msg + " to " + host + ":" + mutilcastSocket.getLocalPort()); | |
} | |
try { | |
byte[] data = (msg + "\n").getBytes(); | |
DatagramPacket hi = new DatagramPacket(data, data.length, InetAddress.getByName(host), mutilcastSocket.getLocalPort()); | |
mutilcastSocket.send(hi); | |
} catch (Exception e) { | |
throw new IllegalStateException(e.getMessage(), e); | |
} | |
} | |
protected void doRegister(URL url) { | |
broadcast(Constants.REGISTER + " " + url.toFullString()); | |
} | |
protected void doUnregister(URL url) { | |
broadcast(Constants.UNREGISTER + " " + url.toFullString()); | |
} | |
protected void doSubscribe(URL url, NotifyListener listener) { | |
if (Constants.ANY_VALUE.equals(url.getServiceInterface())) { | |
admin = true; | |
} | |
if (! Constants.ANY_VALUE.equals(url.getServiceInterface()) | |
&& url.getParameter(Constants.REGISTER_KEY, true)) { | |
register(url, null); | |
} | |
broadcast(Constants.SUBSCRIBE + " " + url.toFullString()); | |
synchronized (listener) { | |
try { | |
listener.wait(url.getParameter(Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT)); | |
} catch (InterruptedException e) { | |
} | |
} | |
} | |
protected void doUnsubscribe(URL url, NotifyListener listener) { | |
if (! Constants.ANY_VALUE.equals(url.getServiceInterface()) | |
&& url.getParameter(Constants.REGISTER_KEY, true)) { | |
unregister(url, null); | |
} | |
broadcast(Constants.UNSUBSCRIBE + " " + url.toFullString()); | |
} | |
public boolean isAvailable() { | |
try { | |
return mutilcastSocket != null; | |
} catch (Throwable t) { | |
return false; | |
} | |
} | |
public void destroy() { | |
super.destroy(); | |
try { | |
if (cleanFuture != null) { | |
cleanFuture.cancel(true); | |
} | |
} catch (Throwable t) { | |
logger.warn(t.getMessage(), t); | |
} | |
try { | |
mutilcastSocket.leaveGroup(mutilcastAddress); | |
mutilcastSocket.close(); | |
} catch (Throwable t) { | |
logger.warn(t.getMessage(), t); | |
} | |
} | |
protected void registered(URL url) { | |
for (Map.Entry<String, Set<NotifyListener>> entry : getSubscribed().entrySet()) { | |
String key = entry.getKey(); | |
URL subscribe = URL.valueOf(key); | |
if (UrlUtils.isMatch(subscribe, url)) { | |
Set<String> urls = notified.get(key); | |
if (urls == null) { | |
notified.putIfAbsent(key, new ConcurrentHashSet<String>()); | |
urls = notified.get(key); | |
} | |
urls.add(url.toFullString()); | |
List<URL> list = toList(urls); | |
for (NotifyListener listener : entry.getValue()) { | |
notify(subscribe, listener, list); | |
synchronized (listener) { | |
listener.notify(); | |
} | |
} | |
} | |
} | |
} | |
protected void unregistered(URL url) { | |
for (Map.Entry<String, Set<NotifyListener>> entry : getSubscribed().entrySet()) { | |
String key = entry.getKey(); | |
URL subscribe = URL.valueOf(key); | |
if (UrlUtils.isMatch(subscribe, url)) { | |
Set<String> urls = notified.get(key); | |
if (urls != null) { | |
urls.remove(url.toFullString()); | |
} | |
List<URL> list = toList(urls); | |
for (NotifyListener listener : entry.getValue()) { | |
notify(subscribe, listener, list); | |
} | |
} | |
} | |
} | |
protected void subscribed(URL url, NotifyListener listener) { | |
List<URL> urls = lookup(url); | |
notify(url, listener, urls); | |
} | |
private List<URL> toList(Set<String> urls) { | |
List<URL> list = new ArrayList<URL>(); | |
if (urls != null && urls.size() > 0) { | |
for (String url : urls) { | |
list.add(URL.valueOf(url)); | |
} | |
} | |
return list; | |
} | |
public void register(URL url, NotifyListener listener) { | |
super.register(url, listener); | |
registered(url); | |
} | |
public void unregister(URL url, NotifyListener listener) { | |
super.unregister(url, listener); | |
unregistered(url); | |
} | |
public void subscribe(URL url, NotifyListener listener) { | |
super.subscribe(url, listener); | |
subscribed(url, listener); | |
} | |
public void unsubscribe(URL url, NotifyListener listener) { | |
super.unsubscribe(url, listener); | |
notified.remove(url.toFullString()); | |
} | |
public Map<String, Set<String>> getNotified() { | |
return notified; | |
} | |
public MulticastSocket getMutilcastSocket() { | |
return mutilcastSocket; | |
} | |
} |