/*
* Copyright 2009 Red Hat, Inc.
*
* Red Hat 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.example.proxy;
import java.net.InetSocketAddress;
import org.jboss.netty.bootstrap.ClientBootstrap;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
import org.jboss.netty.channel.socket.ClientSocketChannelFactory;
/**
* @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
* @author <a href="http://gleamynode.net/">Trustin Lee</a>
* @version $Rev: 2376 $, $Date: 2010-10-25 03:24:20 +0900 (Mon, 25 Oct 2010) $
*/
public class HexDumpProxyInboundHandler extends SimpleChannelUpstreamHandler {
private final ClientSocketChannelFactory cf;
private final String remoteHost;
private final int remotePort;
// This lock guards against the race condition that overrides the
// OP_READ flag incorrectly.
// See the related discussion: http://markmail.org/message/x7jc6mqx6ripynqf
final Object trafficLock = new Object();
private volatile Channel outboundChannel;
public HexDumpProxyInboundHandler(
ClientSocketChannelFactory cf, String remoteHost, int remotePort) {
this.cf = cf;
this.remoteHost = remoteHost;
this.remotePort = remotePort;
}
@Override
public void channelOpen(ChannelHandlerContext ctx, ChannelStateEvent e)
throws Exception {
// Suspend incoming traffic until connected to the remote host.
final Channel inboundChannel = e.getChannel();
inboundChannel.setReadable(false);
// Start the connection attempt.
ClientBootstrap cb = new ClientBootstrap(cf);
cb.getPipeline().addLast("handler", new OutboundHandler(e.getChannel()));
ChannelFuture f = cb.connect(new InetSocketAddress(remoteHost, remotePort));
outboundChannel = f.getChannel();
f.addListener(new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
// Connection attempt succeeded:
// Begin to accept incoming traffic.
inboundChannel.setReadable(true);
} else {
// Close the connection if the connection attempt has failed.
inboundChannel.close();
}
}
});
}
@Override
public void messageReceived(ChannelHandlerContext ctx, final MessageEvent e)
throws Exception {
ChannelBuffer msg = (ChannelBuffer) e.getMessage();
//System.out.println(">>> " + ChannelBuffers.hexDump(msg));
synchronized (trafficLock) {
outboundChannel.write(msg);
// If outboundChannel is saturated, do not read until notified in
// OutboundHandler.channelInterestChanged().
if (!outboundChannel.isWritable()) {
e.getChannel().setReadable(false);
}
}
}
@Override
public void channelInterestChanged(ChannelHandlerContext ctx,
ChannelStateEvent e) throws Exception {
// If inboundChannel is not saturated anymore, continue accepting
// the incoming traffic from the outboundChannel.
synchronized (trafficLock) {
if (e.getChannel().isWritable()) {
outboundChannel.setReadable(true);
}
}
}
@Override
public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e)
throws Exception {
if (outboundChannel != null) {
closeOnFlush(outboundChannel);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
throws Exception {
e.getCause().printStackTrace();
closeOnFlush(e.getChannel());
}
private class OutboundHandler extends SimpleChannelUpstreamHandler {
private final Channel inboundChannel;
OutboundHandler(Channel inboundChannel) {
this.inboundChannel = inboundChannel;
}
@Override
public void messageReceived(ChannelHandlerContext ctx, final MessageEvent e)
throws Exception {
ChannelBuffer msg = (ChannelBuffer) e.getMessage();
//System.out.println("<<< " + ChannelBuffers.hexDump(msg));
synchronized (trafficLock) {
inboundChannel.write(msg);
// If inboundChannel is saturated, do not read until notified in
// HexDumpProxyInboundHandler.channelInterestChanged().
if (!inboundChannel.isWritable()) {
e.getChannel().setReadable(false);
}
}
}
@Override
public void channelInterestChanged(ChannelHandlerContext ctx,
ChannelStateEvent e) throws Exception {
// If outboundChannel is not saturated anymore, continue accepting
// the incoming traffic from the inboundChannel.
synchronized (trafficLock) {
if (e.getChannel().isWritable()) {
inboundChannel.setReadable(true);
}
}
}
@Override
public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e)
throws Exception {
closeOnFlush(inboundChannel);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
throws Exception {
e.getCause().printStackTrace();
closeOnFlush(e.getChannel());
}
}
/**
* Closes the specified channel after all queued write requests are flushed.
*/
static void closeOnFlush(Channel ch) {
if (ch.isConnected()) {
ch.write(ChannelBuffers.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);
}
}
}