Netty server/business logic 实现

package com.netty.examples.discard;

import io.netty.buffer.Unpooled;

import io.netty.channel.ChannelFutureListener;

import io.netty.channel.ChannelHandler.Sharable;

import io.netty.channel.ChannelHandlerContext;

import io.netty.channel.ChannelInboundHandlerAdapter;

import io.netty.util.ReferenceCountUtil;

 

@Sharable

public class DiscardServerHandler extends ChannelInboundHandlerAdapter {

 

@Override

public void channelRead(ChannelHandlerContext ctx, Object msg) {

try {

System.out.println("Server received: " + msg);

ctx.write(msg);

       ctx.flush();

} finally {

       ReferenceCountUtil.release(msg);

}

}

 

@Override

public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {

ctx.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);

}

 

@Override

public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause)

throws Exception {

// Close the connection when an exception is raised.

cause.printStackTrace();

ctx.close();

}

}

 

@Sharable annotation 表明Handler可以在不同Channel之间共享。

ctx.writeAndFlush()方法 "flush" the messages to the remote peer yet.

 

DiscardServerHandler继承自ChannelInboundHandlerAdapter，你必须显示调用方法

ReferenceCountUtil.release(msg)释放资源。