/*
* Copyright (C) 2008 Trustin Heuiseung Lee
*
* This library 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 library 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 library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301 USA
*/
package net.gleamynode.netty.channel.socket.nio;
import static net.gleamynode.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.Set;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.logging.Level;
import java.util.logging.Logger;
import net.gleamynode.netty.channel.AbstractChannelSink;
import net.gleamynode.netty.channel.ChannelEvent;
import net.gleamynode.netty.channel.ChannelException;
import net.gleamynode.netty.channel.ChannelFuture;
import net.gleamynode.netty.channel.ChannelFutureListener;
import net.gleamynode.netty.channel.ChannelPipeline;
import net.gleamynode.netty.channel.ChannelState;
import net.gleamynode.netty.channel.ChannelStateEvent;
import net.gleamynode.netty.channel.MessageEvent;
import net.gleamynode.netty.util.NamePreservingRunnable;
class NioClientSocketPipelineSink extends AbstractChannelSink {
static final Logger logger =
Logger.getLogger(NioClientSocketPipelineSink.class.getName());
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();
channel.writeBuffer.offer(event);
NioWorker.write(channel);
}
}
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)) {
NioWorker worker = nextWorker();
channel.setWorker(worker);
future.setSuccess();
worker.register(channel);
} else {
future.addListener(new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) {
if (future.isCancelled()) {
channel.close();
}
}
});
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 class Boss implements Runnable {
private final AtomicBoolean started = new AtomicBoolean();
private volatile Selector selector;
private final Object selectorGuard = new Object();
Boss() {
super();
}
void register(NioSocketChannel channel) {
boolean firstChannel = started.compareAndSet(false, true);
Selector selector;
if (firstChannel) {
try {
this.selector = selector = Selector.open();
} catch (IOException e) {
throw new ChannelException(
"Failed to create a selector.", e);
}
} else {
selector = this.selector;
if (selector == null) {
do {
Thread.yield();
selector = this.selector;
} while (selector == null);
}
}
if (firstChannel) {
try {
channel.socket.register(selector, SelectionKey.OP_CONNECT, channel);
} catch (ClosedChannelException e) {
throw new ChannelException(
"Failed to register a socket to the selector.", e);
}
bossExecutor.execute(new NamePreservingRunnable(
this,
"New I/O client boss #" + id));
} else {
synchronized (selectorGuard) {
selector.wakeup();
try {
channel.socket.register(selector, SelectionKey.OP_CONNECT, channel);
} catch (ClosedChannelException e) {
throw new ChannelException(
"Failed to register a socket to the selector.", e);
}
}
}
}
public void run() {
boolean shutdown = false;
Selector selector = this.selector;
for (;;) {
synchronized (selectorGuard) {
// This empty synchronization block prevents the selector
// from acquiring its lock.
}
try {
int selectedKeyCount = selector.select(500);
if (selectedKeyCount > 0) {
processSelectedKeys(selector.selectedKeys());
}
if (selector.keys().isEmpty()) {
if (shutdown) {
try {
selector.close();
} catch (IOException e) {
logger.log(
Level.WARNING,
"Failed to close a selector.", e);
} finally {
this.selector = null;
}
started.set(false);
break;
} else {
// Give one more second.
shutdown = true;
}
}
} catch (Throwable t) {
logger.log(
Level.WARNING,
"Unexpected exception in the selector loop.", t);
// Prevent possible consecutive immediate failures.
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// Ignore.
}
}
}
}
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();
NioWorker worker = nextWorker();
ch.setWorker(worker);
ch.connectFuture.setSuccess();
worker.register(ch);
}
} catch (IOException e) {
k.cancel();
fireExceptionCaught(ch, e);
close(k);
}
}
private void close(SelectionKey k) {
NioSocketChannel ch = (NioSocketChannel) k.attachment();
NioWorker.close(ch, ch.getSucceededFuture());
}
}
}