Netty入門（三）之web服務器

Netty入門（三）之web服務器

閱讀前請參考

• Netty入門（一）之webSocket聊天室
• Netty入門（二）之PC聊天室

有了前兩篇的使用基礎，學習本文也很簡單！只須要在前兩文的基礎上稍微改動便可！

Maven依賴

<!-- Netty -->
        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
            <version>4.1.22.Final</version>
        </dependency>

一：啓動類

關於啓動類，須要咱們作的就是自定義端口以及繼承ChannelInitializer類。

/** * Netty服務器啓動 * Create by yster@foxmail.com 2018-05-04 **/
public class HttpServerStartup {
    public void startup() {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup workGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workGroup);
            b.channel(NioServerSocketChannel.class);
            b.childHandler(new MyServerInitializer());    //繼承重寫類
            Channel ch = b.bind(8888).sync().channel();    //自定義端口
            ch.closeFuture().sync();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            //優雅的退出程序
            bossGroup.shutdownGracefully();
            workGroup.shutdownGracefully();
        }
    }

}

二：信道初始化

/** * 信道初始化 * Create by yster@foxmail.com 2018-05-04 **/
public class MyServerInitializer extends ChannelInitializer<SocketChannel> {
    @Override
    public void initChannel(SocketChannel ch) throws Exception {
        ChannelPipeline pipeline = ch.pipeline();  
        /** * http-request解碼器 * http服務器端對request解碼 */  
        pipeline.addLast("decoder", new HttpRequestDecoder());  
        /** * http-response解碼器 * http服務器端對response編碼 */  
        pipeline.addLast("encoder", new HttpResponseEncoder());  
        pipeline.addLast("deflater", new HttpContentCompressor());  
        pipeline.addLast("handler", new MyServerChannelHandler());  
    }
}

值得一提的是，上面信道的處理對post請求而言不太方便獲取參數。

三：綁定處理程序中的信道

/** * 綁定處理程序中的簡單通道 * Create by yster@foxmail.com 2018-05-04 **/
@Sharable
public class MyServerChannelHandler extends SimpleChannelInboundHandler<HttpObject> {

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg){
        if (msg instanceof HttpRequest) {
           //request response都已經獲取到！
           ByteBuf byteBuf = Unpooled.copiedBuffer("Hello".getBytes()); 
　　　　   DefaultFullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1,HttpResponseStatus.OK,byteBuf);
           ctx.channel().writeAndFlush(response);
        }
    }

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

}