/*
* Copyright 2012 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 com.facebook.presto.jdbc.internal.netty.channel.socket.nio;
import com.facebook.presto.jdbc.internal.netty.buffer.ChannelBuffer;
import com.facebook.presto.jdbc.internal.netty.channel.AbstractChannel;
import com.facebook.presto.jdbc.internal.netty.channel.Channel;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelFactory;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelPipeline;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelSink;
import com.facebook.presto.jdbc.internal.netty.channel.MessageEvent;
import com.facebook.presto.jdbc.internal.netty.channel.socket.nio.SocketSendBufferPool.SendBuffer;
import com.facebook.presto.jdbc.internal.netty.util.internal.ThreadLocalBoolean;
import java.net.InetSocketAddress;
import java.nio.channels.SelectableChannel;
import java.nio.channels.WritableByteChannel;
import java.util.Collection;
import java.util.Iterator;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import static com.facebook.presto.jdbc.internal.netty.channel.Channels.*;
abstract class AbstractNioChannel<C extends SelectableChannel & WritableByteChannel> extends AbstractChannel {
/**
* The {@link AbstractNioWorker}.
*/
final AbstractNioWorker worker;
/**
* Monitor object for synchronizing access to the {@link WriteRequestQueue}.
*/
final Object writeLock = new Object();
/**
* WriteTask that performs write operations.
*/
final Runnable writeTask = new WriteTask();
/**
* Indicates if there is a {@link WriteTask} in the task queue.
*/
final AtomicBoolean writeTaskInTaskQueue = new AtomicBoolean();
/**
* Queue of write {@link MessageEvent}s.
*/
final Queue<MessageEvent> writeBufferQueue = new WriteRequestQueue();
/**
* Keeps track of the number of bytes that the {@link WriteRequestQueue} currently
* contains.
*/
final AtomicInteger writeBufferSize = new AtomicInteger();
/**
* Keeps track of the highWaterMark.
*/
final AtomicInteger highWaterMarkCounter = new AtomicInteger();
/**
* The current write {@link MessageEvent}
*/
MessageEvent currentWriteEvent;
SendBuffer currentWriteBuffer;
/**
* Boolean that indicates that write operation is in progress.
*/
boolean inWriteNowLoop;
boolean writeSuspended;
private volatile InetSocketAddress localAddress;
volatile InetSocketAddress remoteAddress;
final C channel;
protected AbstractNioChannel(
Integer id, Channel parent, ChannelFactory factory, ChannelPipeline pipeline,
ChannelSink sink, AbstractNioWorker worker, C ch) {
super(id, parent, factory, pipeline, sink);
this.worker = worker;
channel = ch;
}
protected AbstractNioChannel(
Channel parent, ChannelFactory factory,
ChannelPipeline pipeline, ChannelSink sink, AbstractNioWorker worker, C ch) {
super(parent, factory, pipeline, sink);
this.worker = worker;
channel = ch;
}
/**
* Return the {@link AbstractNioWorker} that handle the IO of the
* {@link AbstractNioChannel}
*
* @return worker
*/
public AbstractNioWorker getWorker() {
return worker;
}
public InetSocketAddress getLocalAddress() {
InetSocketAddress localAddress = this.localAddress;
if (localAddress == null) {
try {
localAddress = getLocalSocketAddress();
if (localAddress.getAddress().isAnyLocalAddress()) {
// Don't cache on a wildcard address so the correct one
// will be cached once the channel is connected/bound
return localAddress;
}
this.localAddress = localAddress;
} catch (Throwable t) {
// Sometimes fails on a closed socket in Windows.
return null;
}
}
return localAddress;
}
public InetSocketAddress getRemoteAddress() {
InetSocketAddress remoteAddress = this.remoteAddress;
if (remoteAddress == null) {
try {
this.remoteAddress = remoteAddress =
getRemoteSocketAddress();
} catch (Throwable t) {
// Sometimes fails on a closed socket in Windows.
return null;
}
}
return remoteAddress;
}
public abstract NioChannelConfig getConfig();
int getRawInterestOps() {
return super.getInterestOps();
}
void setRawInterestOpsNow(int interestOps) {
setInterestOpsNow(interestOps);
}
@Override
public int getInterestOps() {
if (!isOpen()) {
return Channel.OP_WRITE;
}
int interestOps = getRawInterestOps();
int writeBufferSize = this.writeBufferSize.get();
if (writeBufferSize != 0) {
if (highWaterMarkCounter.get() > 0) {
int lowWaterMark = getConfig().getWriteBufferLowWaterMark();
if (writeBufferSize >= lowWaterMark) {
interestOps |= Channel.OP_WRITE;
} else {
interestOps &= ~Channel.OP_WRITE;
}
} else {
int highWaterMark = getConfig().getWriteBufferHighWaterMark();
if (writeBufferSize >= highWaterMark) {
interestOps |= Channel.OP_WRITE;
} else {
interestOps &= ~Channel.OP_WRITE;
}
}
} else {
interestOps &= ~Channel.OP_WRITE;
}
return interestOps;
}
@Override
protected boolean setClosed() {
return super.setClosed();
}
abstract InetSocketAddress getLocalSocketAddress() throws Exception;
abstract InetSocketAddress getRemoteSocketAddress() throws Exception;
private final class WriteRequestQueue implements Queue<MessageEvent> {
private final ThreadLocalBoolean notifying = new ThreadLocalBoolean();
private final Queue<MessageEvent> queue;
public WriteRequestQueue() {
queue = new ConcurrentLinkedQueue<MessageEvent>();
}
public MessageEvent remove() {
return queue.remove();
}
public MessageEvent element() {
return queue.element();
}
public MessageEvent peek() {
return queue.peek();
}
public int size() {
return queue.size();
}
public boolean isEmpty() {
return queue.isEmpty();
}
public Iterator<MessageEvent> iterator() {
return queue.iterator();
}
public Object[] toArray() {
return queue.toArray();
}
public <T> T[] toArray(T[] a) {
return queue.toArray(a);
}
public boolean containsAll(Collection<?> c) {
return queue.containsAll(c);
}
public boolean addAll(Collection<? extends MessageEvent> c) {
return queue.addAll(c);
}
public boolean removeAll(Collection<?> c) {
return queue.removeAll(c);
}
public boolean retainAll(Collection<?> c) {
return queue.retainAll(c);
}
public void clear() {
queue.clear();
}
public boolean add(MessageEvent e) {
return queue.add(e);
}
public boolean remove(Object o) {
return queue.remove(o);
}
public boolean contains(Object o) {
return queue.contains(o);
}
public boolean offer(MessageEvent e) {
boolean success = queue.offer(e);
assert success;
int messageSize = getMessageSize(e);
int newWriteBufferSize = writeBufferSize.addAndGet(messageSize);
int highWaterMark = getConfig().getWriteBufferHighWaterMark();
if (newWriteBufferSize >= highWaterMark) {
if (newWriteBufferSize - messageSize < highWaterMark) {
highWaterMarkCounter.incrementAndGet();
if (!notifying.get()) {
notifying.set(Boolean.TRUE);
fireChannelInterestChanged(AbstractNioChannel.this);
notifying.set(Boolean.FALSE);
}
}
}
return true;
}
public MessageEvent poll() {
MessageEvent e = queue.poll();
if (e != null) {
int messageSize = getMessageSize(e);
int newWriteBufferSize = writeBufferSize.addAndGet(-messageSize);
int lowWaterMark = getConfig().getWriteBufferLowWaterMark();
if (newWriteBufferSize == 0 || newWriteBufferSize < lowWaterMark) {
if (newWriteBufferSize + messageSize >= lowWaterMark) {
highWaterMarkCounter.decrementAndGet();
if (isConnected() && !notifying.get()) {
notifying.set(Boolean.TRUE);
fireChannelInterestChanged(AbstractNioChannel.this);
notifying.set(Boolean.FALSE);
}
}
}
}
return e;
}
private int getMessageSize(MessageEvent e) {
Object m = e.getMessage();
if (m instanceof ChannelBuffer) {
return ((ChannelBuffer) m).readableBytes();
}
return 0;
}
}
private final class WriteTask implements Runnable {
WriteTask() {
}
public void run() {
writeTaskInTaskQueue.set(false);
worker.writeFromTaskLoop(AbstractNioChannel.this);
}
}
}