/*
* Copyright 2011 The Netty Project
*
* The Netty Project licenses this file to you 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 org.jboss.netty.channel.socket.oio;
import static org.jboss.netty.channel.Channels.*;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.socket.Worker;
import org.jboss.netty.util.internal.QueueFactory;
import java.io.IOException;
import java.util.Queue;
/**
* Abstract base class for Oio-Worker implementations
*
* @param <C> {@link AbstractOioChannel}
*/
abstract class AbstractOioWorker<C extends AbstractOioChannel> implements Worker {
private final Queue<Runnable> eventQueue = QueueFactory.createQueue(Runnable.class);
protected final C channel;
/**
* If this worker has been started thread will be a reference to the thread
* used when starting. i.e. the current thread when the run method is executed.
*/
protected volatile Thread thread;
private volatile boolean done;
public AbstractOioWorker(C channel) {
this.channel = channel;
channel.worker = this;
}
public void run() {
thread = channel.workerThread = Thread.currentThread();
while (channel.isOpen()) {
synchronized (channel.interestOpsLock) {
while (!channel.isReadable()) {
try {
// notify() is not called at all.
// close() and setInterestOps() calls Thread.interrupt()
channel.interestOpsLock.wait();
} catch (InterruptedException e) {
if (!channel.isOpen()) {
break;
}
}
}
}
boolean cont = false;
try {
cont = process();
} catch (Throwable t) {
if (!channel.isSocketClosed()) {
fireExceptionCaught(channel, t);
}
} finally {
processEventQueue();
if (!cont) {
break;
}
}
}
// Setting the workerThread to null will prevent any channel
// operations from interrupting this thread from now on.
channel.workerThread = null;
// Clean up.
close(channel, succeededFuture(channel), true);
// Mark the worker event loop as done so we know that we need to run tasks directly and not queue them
// See #287
done = true;
// just to make we don't have something left
processEventQueue();
}
static boolean isIoThread(AbstractOioChannel channel) {
return Thread.currentThread() == channel.workerThread;
}
public void executeInIoThread(Runnable task) {
// check if the current thread is the worker thread
//
// Also check if the event loop of the worker is complete. If so we need to run the task now.
// See #287
if (Thread.currentThread() == thread || done) {
task.run();
} else {
boolean added = eventQueue.offer(task);
if (added) {
// as we set the SO_TIMEOUT to 1 second this task will get picked up in 1 second at latest
}
}
}
private void processEventQueue() {
for (;;) {
final Runnable task = eventQueue.poll();
if (task == null) {
break;
}
task.run();
}
}
/**
* Process the incoming messages and also is responsible for call {@link Channels#fireMessageReceived(Channel, Object)} once a message
* was processed without errors.
*
* @return continue returns <code>true</code> as long as this worker should continue to try processing incoming messages
* @throws IOException
*/
abstract boolean process() throws IOException;
static void setInterestOps(
AbstractOioChannel channel, ChannelFuture future, int interestOps) {
boolean iothread = isIoThread(channel);
// Override OP_WRITE flag - a user cannot change this flag.
interestOps &= ~Channel.OP_WRITE;
interestOps |= channel.getInterestOps() & Channel.OP_WRITE;
boolean changed = false;
try {
if (channel.getInterestOps() != interestOps) {
if ((interestOps & Channel.OP_READ) != 0) {
channel.setInterestOpsNow(Channel.OP_READ);
} else {
channel.setInterestOpsNow(Channel.OP_NONE);
}
changed = true;
}
future.setSuccess();
if (changed) {
synchronized (channel.interestOpsLock) {
channel.setInterestOpsNow(interestOps);
// Notify the worker so it stops or continues reading.
Thread currentThread = Thread.currentThread();
Thread workerThread = channel.workerThread;
if (workerThread != null && currentThread != workerThread) {
workerThread.interrupt();
}
}
if (iothread) {
fireChannelInterestChanged(channel);
} else {
fireChannelInterestChangedLater(channel);
}
}
} catch (Throwable t) {
future.setFailure(t);
if (iothread) {
fireExceptionCaught(channel, t);
} else {
fireExceptionCaughtLater(channel, t);
}
}
}
static void close(AbstractOioChannel channel, ChannelFuture future) {
close(channel, future, isIoThread(channel));
}
private static void close(AbstractOioChannel channel, ChannelFuture future, boolean iothread) {
boolean connected = channel.isConnected();
boolean bound = channel.isBound();
try {
channel.closeSocket();
if (channel.setClosed()) {
future.setSuccess();
if (connected) {
// Notify the worker so it stops reading.
Thread currentThread = Thread.currentThread();
Thread workerThread = channel.workerThread;
if (workerThread != null && currentThread != workerThread) {
workerThread.interrupt();
}
if (iothread) {
fireChannelDisconnected(channel);
} else {
fireChannelDisconnectedLater(channel);
}
}
if (bound) {
if (iothread) {
fireChannelUnbound(channel);
} else {
fireChannelUnboundLater(channel);
}
}
if (iothread) {
fireChannelClosed(channel);
} else {
fireChannelClosedLater(channel);
}
} else {
future.setSuccess();
}
} catch (Throwable t) {
future.setFailure(t);
if (iothread) {
fireExceptionCaught(channel, t);
} else {
fireExceptionCaughtLater(channel, t);
}
}
}
}