/*
* JBoss, Home of Professional Open Source
*
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* by the @author tags. See the COPYRIGHT.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.netty.channel.socket.nio;
import static org.jboss.netty.channel.Channels.*;
import java.io.IOException;
import java.net.SocketAddress;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.util.Iterator;
import java.util.Queue;
import java.util.Set;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import org.jboss.netty.channel.AbstractChannelSink;
import org.jboss.netty.channel.ChannelEvent;
import org.jboss.netty.channel.ChannelException;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelState;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.logging.InternalLogger;
import org.jboss.netty.logging.InternalLoggerFactory;
import org.jboss.netty.util.LinkedTransferQueue;
import org.jboss.netty.util.ThreadRenamingRunnable;
/**
*
* @author The Netty Project (netty-dev@lists.jboss.org)
* @author Trustin Lee (tlee@redhat.com)
*
* @version $Rev: 988 $, $Date: 2009-03-04 23:30:47 +0900 (Wed, 04 Mar 2009) $
*
*/
class NioClientSocketPipelineSink extends AbstractChannelSink {
static final InternalLogger logger =
InternalLoggerFactory.getInstance(NioClientSocketPipelineSink.class);
private static final AtomicInteger nextId = new AtomicInteger();
final int id = nextId.incrementAndGet();
final Executor bossExecutor;
private final Boss boss = new Boss();
private final NioWorker[] workers;
private final AtomicInteger workerIndex = new AtomicInteger();
NioClientSocketPipelineSink(
Executor bossExecutor, Executor workerExecutor, int workerCount) {
this.bossExecutor = bossExecutor;
workers = new NioWorker[workerCount];
for (int i = 0; i < workers.length; i ++) {
workers[i] = new NioWorker(id, i + 1, workerExecutor);
}
}
public void eventSunk(
ChannelPipeline pipeline, ChannelEvent e) throws Exception {
if (e instanceof ChannelStateEvent) {
ChannelStateEvent event = (ChannelStateEvent) e;
NioClientSocketChannel channel =
(NioClientSocketChannel) event.getChannel();
ChannelFuture future = event.getFuture();
ChannelState state = event.getState();
Object value = event.getValue();
switch (state) {
case OPEN:
if (Boolean.FALSE.equals(value)) {
NioWorker.close(channel, future);
}
break;
case BOUND:
if (value != null) {
bind(channel, future, (SocketAddress) value);
} else {
NioWorker.close(channel, future);
}
break;
case CONNECTED:
if (value != null) {
connect(channel, future, (SocketAddress) value);
} else {
NioWorker.close(channel, future);
}
break;
case INTEREST_OPS:
NioWorker.setInterestOps(channel, future, ((Integer) value).intValue());
break;
}
} else if (e instanceof MessageEvent) {
MessageEvent event = (MessageEvent) e;
NioSocketChannel channel = (NioSocketChannel) event.getChannel();
boolean offered = channel.writeBuffer.offer(event);
assert offered;
NioWorker.write(channel, true);
}
}
private void bind(
NioClientSocketChannel channel, ChannelFuture future,
SocketAddress localAddress) {
try {
channel.socket.socket().bind(localAddress);
channel.boundManually = true;
future.setSuccess();
fireChannelBound(channel, channel.getLocalAddress());
} catch (Throwable t) {
future.setFailure(t);
fireExceptionCaught(channel, t);
}
}
private void connect(
final NioClientSocketChannel channel, ChannelFuture future,
SocketAddress remoteAddress) {
try {
if (channel.socket.connect(remoteAddress)) {
channel.worker.register(channel, future);
} else {
future.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
channel.connectFuture = future;
boss.register(channel);
}
} catch (Throwable t) {
future.setFailure(t);
fireExceptionCaught(channel, t);
}
}
NioWorker nextWorker() {
return workers[Math.abs(
workerIndex.getAndIncrement() % workers.length)];
}
private final class Boss implements Runnable {
volatile Selector selector;
private boolean started;
private final AtomicBoolean wakenUp = new AtomicBoolean();
private final Object startStopLock = new Object();
private final Queue<Runnable> registerTaskQueue = new LinkedTransferQueue<Runnable>();
Boss() {
super();
}
void register(NioSocketChannel channel) {
Runnable registerTask = new RegisterTask(this, channel);
Selector selector;
synchronized (startStopLock) {
if (!started) {
// Open a selector if this worker didn't start yet.
try {
this.selector = selector = Selector.open();
} catch (Throwable t) {
throw new ChannelException(
"Failed to create a selector.", t);
}
// Start the worker thread with the new Selector.
boolean success = false;
try {
bossExecutor.execute(new ThreadRenamingRunnable(
this, "New I/O client boss #" + id));
success = true;
} finally {
if (!success) {
// Release the Selector if the execution fails.
try {
selector.close();
} catch (Throwable t) {
logger.warn("Failed to close a selector.", t);
}
this.selector = selector = null;
// The method will return to the caller at this point.
}
}
} else {
// Use the existing selector if this worker has been started.
selector = this.selector;
}
assert selector != null && selector.isOpen();
started = true;
boolean offered = registerTaskQueue.offer(registerTask);
assert offered;
}
if (wakenUp.compareAndSet(false, true)) {
selector.wakeup();
}
}
public void run() {
boolean shutdown = false;
Selector selector = this.selector;
for (;;) {
wakenUp.set(false);
try {
int selectedKeyCount = selector.select(500);
// Wake up immediately in the next turn if someone might
// have waken up the selector between 'wakenUp.set(false)'
// and 'selector.select(...)'.
if (wakenUp.get()) {
selector.wakeup();
}
processRegisterTaskQueue();
if (selectedKeyCount > 0) {
processSelectedKeys(selector.selectedKeys());
}
// Exit the loop when there's nothing to handle.
// The shutdown flag is used to delay the shutdown of this
// loop to avoid excessive Selector creation when
// connection attempts are made in a one-by-one manner
// instead of concurrent manner.
if (selector.keys().isEmpty()) {
if (shutdown ||
bossExecutor instanceof ExecutorService && ((ExecutorService) bossExecutor).isShutdown()) {
synchronized (startStopLock) {
if (registerTaskQueue.isEmpty() && selector.keys().isEmpty()) {
started = false;
try {
selector.close();
} catch (IOException e) {
logger.warn(
"Failed to close a selector.", e);
} finally {
this.selector = null;
}
break;
} else {
shutdown = false;
}
}
} else {
// Give one more second.
shutdown = true;
}
} else {
shutdown = false;
}
} catch (Throwable t) {
logger.warn(
"Unexpected exception in the selector loop.", t);
// Prevent possible consecutive immediate failures.
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// Ignore.
}
}
}
}
private void processRegisterTaskQueue() {
for (;;) {
final Runnable task = registerTaskQueue.poll();
if (task == null) {
break;
}
task.run();
}
}
private void processSelectedKeys(Set<SelectionKey> selectedKeys) {
for (Iterator<SelectionKey> i = selectedKeys.iterator(); i.hasNext();) {
SelectionKey k = i.next();
i.remove();
if (!k.isValid()) {
close(k);
continue;
}
if (k.isConnectable()) {
connect(k);
}
}
}
private void connect(SelectionKey k) {
NioClientSocketChannel ch = (NioClientSocketChannel) k.attachment();
try {
if (ch.socket.finishConnect()) {
k.cancel();
ch.worker.register(ch, ch.connectFuture);
}
} catch (Throwable t) {
ch.connectFuture.setFailure(t);
fireExceptionCaught(ch, t);
close(k);
}
}
private void close(SelectionKey k) {
k.cancel();
NioSocketChannel ch = (NioSocketChannel) k.attachment();
NioWorker.close(ch, succeededFuture(ch));
}
}
private static final class RegisterTask implements Runnable {
private final Boss boss;
private final NioSocketChannel channel;
RegisterTask(Boss boss, NioSocketChannel channel) {
this.boss = boss;
this.channel = channel;
}
public void run() {
try {
channel.socket.register(
boss.selector, SelectionKey.OP_CONNECT, channel);
} catch (ClosedChannelException e) {
throw new ChannelException(
"Failed to register a socket to the selector.", e);
}
}
}
}