Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF 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.alibaba.dubbo.remoting.transport.netty; import com.alibaba.dubbo.common.URL; import com.alibaba.dubbo.common.utils.NetUtils; import com.alibaba.dubbo.remoting.Channel; import com.alibaba.dubbo.remoting.ChannelHandler; import io.netty.channel.ChannelDuplexHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelPromise; import java.net.InetSocketAddress; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; /** * NettyClientHandler */ @io.netty.channel.ChannelHandler.Sharable public class NettyServerHandler extends ChannelDuplexHandler { private final Map<String, Channel> channels = new ConcurrentHashMap<String, Channel>(); // <ip:port, channel> private final URL url; private final ChannelHandler handler; public NettyServerHandler(URL url, ChannelHandler handler) { if (url == null) { throw new IllegalArgumentException("url == null"); } if (handler == null) { throw new IllegalArgumentException("handler == null"); } this.url = url; this.handler = handler; } public Map<String, Channel> getChannels() { return channels; } @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { ctx.fireChannelActive(); NettyChannel channel = NettyChannel.getOrAddChannel(ctx.channel(), url, handler); try { if (channel != null) { channels.put(NetUtils.toAddressString((InetSocketAddress) ctx.channel().remoteAddress()), channel); } handler.connected(channel); } finally { NettyChannel.removeChannelIfDisconnected(ctx.channel()); } } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { NettyChannel channel = NettyChannel.getOrAddChannel(ctx.channel(), url, handler); try { channels.remove(NetUtils.toAddressString((InetSocketAddress) ctx.channel().remoteAddress())); handler.disconnected(channel); } finally { NettyChannel.removeChannelIfDisconnected(ctx.channel()); } } @Override public void disconnect(ChannelHandlerContext ctx, ChannelPromise future) throws Exception { } @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { NettyChannel channel = NettyChannel.getOrAddChannel(ctx.channel(), url, handler); try { handler.received(channel, msg); } finally { NettyChannel.removeChannelIfDisconnected(ctx.channel()); } } @Override public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception { super.write(ctx, msg, promise); NettyChannel channel = NettyChannel.getOrAddChannel(ctx.channel(), url, handler); try { handler.sent(channel, msg); } finally { NettyChannel.removeChannelIfDisconnected(ctx.channel()); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { NettyChannel channel = NettyChannel.getOrAddChannel(ctx.channel(), url, handler); try { handler.caught(channel, cause); } finally { NettyChannel.removeChannelIfDisconnected(ctx.channel()); } } }