@Override
protected void registerTask(AbstractNioChannel channel, ChannelFuture future) {
final SocketAddress localAddress = channel.getLocalAddress();
if (localAddress == null) {
if (future != null) {
future.setFailure(new ClosedChannelException());
}
close(channel, succeededFuture(channel));
return;
}
try {
synchronized (channel.interestOpsLock) {
channel.getJdkChannel().register(selector, channel.getRawInterestOps(), channel);
}
if (future != null) {
future.setSuccess();
}
} catch (final ClosedChannelException e) {
if (future != null) {
future.setFailure(e);
}
close(channel, succeededFuture(channel));
throw new ChannelException("Failed to register a socket to the selector.", e);
}
}
@Override
public void writeFromUserCode(final AbstractNioChannel channel) {
/*
* Note that we are not checking if the channel is connected. Connected
* has a different meaning in UDP and means that the channels socket is
* configured to only send and receive from a given remote peer.
*/
if (!channel.isBound()) {
cleanUpWriteBuffer(channel);
return;
}
if (scheduleWriteIfNecessary(channel)) {
return;
}
// From here, we are sure Thread.currentThread() == workerThread.
if (channel.writeSuspended) {
return;
}
if (channel.inWriteNowLoop) {
return;
}
write0(channel);
}
/**
* Writes the outgoing {@link DatagramPacket} to the channel. The intended receiver of the
* datagram packet must be set in the <code>data</code> using {@link
* DatagramPacket#setReceiver(SocketAddress)}.
*/
@Override
public void write(Object data, SelectionKey key) {
super.write(data, key);
}
@Override
protected void write0(final AbstractNioChannel channel) {
boolean addOpWrite = false;
boolean removeOpWrite = false;
long writtenBytes = 0;
final SendBufferPool sendBufferPool = this.sendBufferPool;
final DatagramChannel ch = ((NioDatagramChannel) channel).getJdkChannel().getChannel();
final Queue<MessageEvent> writeBuffer = channel.writeBufferQueue;
final int writeSpinCount = channel.getConfig().getWriteSpinCount();
synchronized (channel.writeLock) {
// inform the channel that write is in-progress
channel.inWriteNowLoop = true;
// loop forever...
for (; ; ) {
MessageEvent evt = channel.currentWriteEvent;
SendBuffer buf;
if (evt == null) {
if ((channel.currentWriteEvent = evt = writeBuffer.poll()) == null) {
removeOpWrite = true;
channel.writeSuspended = false;
break;
}
channel.currentWriteBuffer = buf = sendBufferPool.acquire(evt.getMessage());
} else {
buf = channel.currentWriteBuffer;
}
try {
long localWrittenBytes = 0;
SocketAddress raddr = evt.getRemoteAddress();
if (raddr == null) {
for (int i = writeSpinCount; i > 0; i--) {
localWrittenBytes = buf.transferTo(ch);
if (localWrittenBytes != 0) {
writtenBytes += localWrittenBytes;
break;
}
if (buf.finished()) {
break;
}
}
} else {
for (int i = writeSpinCount; i > 0; i--) {
localWrittenBytes = buf.transferTo(ch, raddr);
if (localWrittenBytes != 0) {
writtenBytes += localWrittenBytes;
break;
}
if (buf.finished()) {
break;
}
}
}
if (localWrittenBytes > 0 || buf.finished()) {
// Successful write - proceed to the next message.
buf.release();
ChannelFuture future = evt.getFuture();
channel.currentWriteEvent = null;
channel.currentWriteBuffer = null;
evt = null;
buf = null;
future.setSuccess();
} else {
// Not written at all - perhaps the kernel buffer is full.
addOpWrite = true;
channel.writeSuspended = true;
break;
}
} catch (final AsynchronousCloseException e) {
// Doesn't need a user attention - ignore.
} catch (final Throwable t) {
buf.release();
ChannelFuture future = evt.getFuture();
channel.currentWriteEvent = null;
channel.currentWriteBuffer = null;
buf = null;
evt = null;
future.setFailure(t);
fireExceptionCaught(channel, t);
}
}
channel.inWriteNowLoop = false;
// Initially, the following block was executed after releasing
// the writeLock, but there was a race condition, and it has to be
// executed before releasing the writeLock:
//
// https://issues.jboss.org/browse/NETTY-410
//
if (addOpWrite) {
setOpWrite(channel);
} else if (removeOpWrite) {
clearOpWrite(channel);
}
}
Channels.fireWriteComplete(channel, writtenBytes);
}
