FixedLengthFrameDecoder 定长解码器的使用

FixedLengthFrameDecoder 定长解码器的使用

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.FixedLengthFrameDecoder;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;

import java.net.InetSocketAddress;

/**
 * FixedLengthFrameDecoder 定长解码器的使用
 * 客户端使用命令行：
 *   telnet localhost 8080   通过telnet连接服务端
 *   set localecho      打开本地回显功能
 *
 */
public class EchoServer2 {
    public static void main(String...args) throws InterruptedException {
        EventLoopGroup parent = new NioEventLoopGroup();
        EventLoopGroup child = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(parent, child)
                    .localAddress(new InetSocketAddress(8080))
                    .channel(NioServerSocketChannel.class)
                    .option(ChannelOption.SO_BACKLOG, 100)
                    .handler(new LoggingHandler(LogLevel.INFO))
                    .childHandler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            ch.pipeline().addLast(new FixedLengthFrameDecoder(20));
                            ch.pipeline().addLast(new StringDecoder());
                            ch.pipeline().addLast(new EchoServerHandler());
                        }
                    });
            ChannelFuture f = b.bind().sync();
            f.channel().closeFuture().sync();
        }finally {
            parent.shutdownGracefully().sync();
            child.shutdownGracefully().sync();
        }
    }

    @ChannelHandler.Sharable
    private static class EchoServerHandler extends ChannelInboundHandlerAdapter{

        @Override
        public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
            System.out.println("The server receive order:" + msg);
        }

        @Override
        public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
            cause.printStackTrace();
            ctx.close();
        }
    }
}

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.FixedLengthFrameDecoder;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;

import java.net.InetSocketAddress;

/**
 * FixedLengthFrameDecoder 定长解码器的使用
 * 客户端使用命令行：
 *   telnet localhost 8080   通过telnet连接服务端
 *   set localecho      打开本地回显功能
 *
 */
public class EchoServer2 {
    public static void main(String...args) throws InterruptedException {
        EventLoopGroup parent = new NioEventLoopGroup();
        EventLoopGroup child = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(parent, child)
                    .localAddress(new InetSocketAddress(8080))
                    .channel(NioServerSocketChannel.class)
                    .option(ChannelOption.SO_BACKLOG, 100)
                    .handler(new LoggingHandler(LogLevel.INFO))
                    .childHandler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            ch.pipeline().addLast(new FixedLengthFrameDecoder(20));
                            ch.pipeline().addLast(new StringDecoder());
                            ch.pipeline().addLast(new EchoServerHandler());
                        }
                    });
            ChannelFuture f = b.bind().sync();
            f.channel().closeFuture().sync();
        }finally {
            parent.shutdownGracefully().sync();
            child.shutdownGracefully().sync();
        }
    }

    @ChannelHandler.Sharable
    private static class EchoServerHandler extends ChannelInboundHandlerAdapter{

        @Override
        public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
            System.out.println("The server receive order:" + msg);
        }

        @Override
        public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
            cause.printStackTrace();
            ctx.close();
        }
    }
}