Netty权威指南 第2版学习笔记10——实现HTTP服务

HttpServer

import org.apache.log4j.Logger;import io.netty.bootstrap.ServerBootstrap;import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioServerSocketChannel;import io.netty.handler.codec.http.HttpRequestDecoder; import io.netty.handler.codec.http.HttpResponseEncoder; public class HttpServer {    private static Logger log = Logger.getLogger(HttpServer.class);    public void start(int port) throws Exception {        EventLoopGroup bossGroup = new NioEventLoopGroup();        EventLoopGroup workerGroup = new NioEventLoopGroup();        try {            ServerBootstrap b = new ServerBootstrap();            b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class)                    .childHandler(new ChannelInitializer<SocketChannel>() {                                @Override                                public void initChannel(SocketChannel ch) throws Exception {                                    // server端发送的是httpResponse，所以要使用HttpResponseEncoder进行编码                                    ch.pipeline().addLast(new HttpResponseEncoder());                                    // server端接收到的是httpRequest，所以要使用HttpRequestDecoder进行解码                                    ch.pipeline().addLast(new HttpRequestDecoder());                                    ch.pipeline().addLast(new HttpServerInboundHandler());                                }                            }).option(ChannelOption.SO_BACKLOG, 128)                     .childOption(ChannelOption.SO_KEEPALIVE, true);            ChannelFuture f = b.bind(port).sync();            f.channel().closeFuture().sync();        } finally {            workerGroup.shutdownGracefully();            bossGroup.shutdownGracefully();        }    }    public static void main(String[] args) throws Exception {        HttpServer server = new HttpServer();        log.info("Http Server listening on 8844 ...");        server.start(8844);    }}

HttpServerInboundHandler

import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION;import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_LENGTH;import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;import static io.netty.handler.codec.http.HttpResponseStatus.OK;import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;import org.apache.log4j.Logger;import io.netty.buffer.ByteBuf;import io.netty.buffer.Unpooled;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.ChannelInboundHandlerAdapter;import io.netty.handler.codec.http.DefaultFullHttpResponse;import io.netty.handler.codec.http.FullHttpResponse;import io.netty.handler.codec.http.HttpContent;import io.netty.handler.codec.http.HttpHeaders;import io.netty.handler.codec.http.HttpHeaders.Values;import io.netty.handler.codec.http.HttpRequest;@SuppressWarnings("deprecation")public class HttpServerInboundHandler extends ChannelInboundHandlerAdapter {    private static Logger log = Logger.getLogger(HttpServerInboundHandler.class);    private HttpRequest request;    @Override    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {        if (msg instanceof HttpRequest) {            request = (HttpRequest) msg;            String uri = request.getUri();            System.out.println("Uri:" + uri);        }        if (msg instanceof HttpContent) {            HttpContent content = (HttpContent) msg;            ByteBuf buf = content.content();            System.out.println(buf.toString(io.netty.util.CharsetUtil.UTF_8));            buf.release();            String res = "Hello World";            FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1,OK, Unpooled.wrappedBuffer(res.getBytes("UTF-8")));            response.headers().set(CONTENT_TYPE, "text/plain");            response.headers().set(CONTENT_LENGTH,response.content().readableBytes());            if (HttpHeaders.isKeepAlive(request)) {                response.headers().set(CONNECTION, Values.KEEP_ALIVE);            }            ctx.write(response);            ctx.flush();        }    }    @Override    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {        ctx.flush();    }    @Override    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {        log.error(cause.getMessage());        ctx.close();    }}