netty5/example/src/main/java/io/netty/example/proxy/HexDumpProxyFrontendHandler...

104 lines
3.6 KiB
Java

/*
* 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 io.netty.example.proxy;
import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelOption;
public class HexDumpProxyFrontendHandler extends ChannelInboundHandlerAdapter {
private final String remoteHost;
private final int remotePort;
private volatile Channel outboundChannel;
public HexDumpProxyFrontendHandler(String remoteHost, int remotePort) {
this.remoteHost = remoteHost;
this.remotePort = remotePort;
}
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
final Channel inboundChannel = ctx.channel();
// Start the connection attempt.
Bootstrap b = new Bootstrap();
b.group(inboundChannel.eventLoop())
.channel(ctx.channel().getClass())
.handler(new HexDumpProxyBackendHandler(inboundChannel))
.option(ChannelOption.AUTO_READ, false);
ChannelFuture f = b.connect(remoteHost, remotePort);
outboundChannel = f.channel();
f.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
// connection complete start to read first data
inboundChannel.read();
} else {
// Close the connection if the connection attempt has failed.
inboundChannel.close();
}
}
});
}
@Override
public void channelRead(final ChannelHandlerContext ctx, Object msg) throws Exception {
if (outboundChannel.isActive()) {
outboundChannel.writeAndFlush(msg).addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
// was able to flush out data, start to read the next chunk
ctx.channel().read();
} else {
future.channel().close();
}
}
});
}
}
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
if (outboundChannel != null) {
closeOnFlush(outboundChannel);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
cause.printStackTrace();
closeOnFlush(ctx.channel());
}
/**
* Closes the specified channel after all queued write requests are flushed.
*/
static void closeOnFlush(Channel ch) {
if (ch.isActive()) {
ch.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);
}
}
}