Netty Getting Started instance

Timeserver.java

 PackageNetty.timeserver.server;ImportIo.netty.bootstrap.ServerBootstrap;Importio.netty.channel.ChannelFuture;ImportIo.netty.channel.ChannelInitializer;Importio.netty.channel.ChannelOption;ImportIo.netty.channel.EventLoopGroup;ImportIo.netty.channel.nio.NioEventLoopGroup;ImportIo.netty.channel.socket.SocketChannel;ImportIo.netty.channel.socket.nio.NioServerSocketChannel; Public classTimeserver { Public voidBindintPortthrowsException {eventloopgroup bossgroup=NewNioeventloopgroup (); Eventloopgroup Workergroup=NewNioeventloopgroup (); Try {            //Configure the server's NIO thread rentalServerbootstrap B =NewServerbootstrap (); B.group (Bossgroup, Workergroup). Channel (Nioserversocketchannel.class). Option (Channeloption.so_backlog,1024). Childhandler (NewChildchannelhandler ()); //bind port, synchronization waits for successChannelfuture f =B.bind (port). sync (); //wait for the server to listen port shutdownF.channel (). Closefuture (). sync (); } finally {            //graceful exit, releasing thread pool resourcesbossgroup.shutdowngracefully ();        Workergroup.shutdowngracefully (); }    }    Private classChildchannelhandlerextendsChannelinitializer<socketchannel>{@Overrideprotected voidInitchannel (Socketchannel arg0)throwsException {System.out.println ("Server Initchannel.."); Arg0.pipeline (). AddLast (NewTimeserverhandler ()); }    }     Public Static voidMain (string[] args)throwsException {intPort = 9000; if(Args! =NULL&& args.length > 0) {            Try{Port= Integer.valueof (args[0]); } Catch(NumberFormatException e) {}}Newtimeserver (). bind (port); }}

Timeserverhandler.java

 PackageNetty.timeserver.server;Importjava.util.Date;ImportIo.netty.buffer.ByteBuf;Importio.netty.buffer.Unpooled;ImportIo.netty.channel.ChannelHandlerContext;ImportIo.netty.channel.ChannelInboundHandlerAdapter; Public classTimeserverhandlerextendsChannelinboundhandleradapter {@Override Public voidChannelread (Channelhandlercontext ctx, Object msg)throwsException {System.out.println ("Server Channelread.."); Bytebuf buf=(BYTEBUF) msg; byte[] req =New byte[Buf.readablebytes ()];        Buf.readbytes (req); String Body=NewString (req, "UTF-8"); System.out.println ("The time server receive order:" +body); String currenttime= "QUERY time ORDER". Equalsignorecase (body)?NewDate (System.currenttimemillis ()). ToString ():"Bad ORDER"; Bytebuf resp=Unpooled.copiedbuffer (Currenttime.getbytes ());    Ctx.write (RESP); } @Override Public voidChannelreadcomplete (Channelhandlercontext ctx)throwsException {System.out.println ("Server Channelreadcomplete.."); Ctx.flush ();//data is sent to Socketchannel after refresh} @Override Public voidexceptioncaught (Channelhandlercontext ctx, throwable cause)throwsException {System.out.println ("Server Exceptioncaught..");    Ctx.close (); }}

Timeclient.java

 Packagenetty.timeserver.client;ImportIo.netty.bootstrap.Bootstrap;Importio.netty.channel.ChannelFuture;ImportIo.netty.channel.ChannelInitializer;Importio.netty.channel.ChannelOption;ImportIo.netty.channel.EventLoopGroup;ImportIo.netty.channel.nio.NioEventLoopGroup;ImportIo.netty.channel.socket.SocketChannel;ImportIo.netty.channel.socket.nio.NioSocketChannel; Public classtimeclient { Public voidConnectintPort, String host)throwsException {//Configuring client NiO thread GroupsEventloopgroup Group =NewNioeventloopgroup (); Try{Bootstrap b=NewBootstrap (); B.group (Group). Channel (Niosocketchannel.class). Option (Channeloption.tcp_nodelay,true). Handler (NewChannelinitializer<socketchannel>() {@Overrideprotected voidInitchannel (Socketchannel arg0)throwsException {System.out.println ("Client Initchannel."); Arg0.pipeline (). AddLast (NewTimeclienthandler ());            }                    }); //initiating an asynchronous join operationChannelfuture f =B.connect (host, port). sync (); //waiting for client link to closeF.channel (). Closefuture (). sync (); } finally {            //Graceful exit, free NIO thread groupgroup.shutdowngracefully (); }    }     Public Static voidMain (string[] args)throwsException {intPort = 9000; if(Args! =NULL&& args.length > 0) {            Try{Port= Integer.parseint (args[0]); } Catch(Exception e) {}}NewTimeclient (). Connect (port, "127.0.0.1"); }}

Timeclienthandler.java

 Packagenetty.timeserver.client;ImportJava.util.logging.Logger;ImportIo.netty.buffer.ByteBuf;Importio.netty.buffer.Unpooled;ImportIo.netty.channel.ChannelHandlerContext;ImportIo.netty.channel.ChannelInboundHandlerAdapter; Public classTimeclienthandlerextendsChannelinboundhandleradapter {Private Static FinalLogger Logger =Logger. GetLogger (Timeclienthandler.class. GetName ()); Private FinalBytebuf Firstmessage;  PublicTimeclienthandler () {byte[] req = "QUERY time ORDER". GetBytes (); Firstmessage=Unpooled.buffer (req.length);    Firstmessage.writebytes (req); } @Override Public voidChannelactive (Channelhandlercontext ctx)throwsException {//after establishing a connection with the serverSYSTEM.OUT.PRINTLN ("Client channelactive ...");    Ctx.writeandflush (Firstmessage); } @Override Public voidChannelread (Channelhandlercontext ctx, Object msg)throwsException {System.out.println ("Client Channelread."); //after the server returns the messageBytebuf buf =(BYTEBUF) msg; byte[] req =New byte[Buf.readablebytes ()];        Buf.readbytes (req); String Body=NewString (req, "UTF-8"); System.out.println ("Now is:" +body); } @Override Public voidexceptioncaught (Channelhandlercontext ctx, throwable cause)throwsException {System.out.println ("Client exceptioncaught."); //Freeing ResourcesLogger.warning ("Unexpected exception from downstream:" +cause.getmessage ());    Ctx.close (); }}