Netty系列文章之构建HTTP(HTTPS)应用程序

public class HttpHelloWorldServer {


    static final boolean SSL = System.getProperty("ssl") != null;
    static final int PORT = Integer.parseInt(System.getProperty("port", SSL ? "8443" : "8080"));

    public static void main(String[] args) throws Exception {
        final SslContext sslContext;
        //判断SSL是否为true,为true表示使用HTTPS连接，反之，使用HTTP
        if (SSL) {
            //使用Netty自带的证书工具生成一个数字证书
            SelfSignedCertificate certificate = new SelfSignedCertificate();
            sslContext = SslContextBuilder.forServer(certificate.certificate(), certificate.privateKey()).build();
        } else {
            sslContext = null;
        }
        EventLoopGroup boss = new NioEventLoopGroup(1);
        EventLoopGroup worker = new NioEventLoopGroup();
        try {
            ServerBootstrap bootstrap = new ServerBootstrap();
            bootstrap.group(boss, worker)
                    .channel(NioServerSocketChannel.class)
                    .handler(new LoggingHandler(LogLevel.INFO))
                    .childHandler(new ChannelInitializer<SocketChannel>() {
                        @Override
                        protected void initChannel(SocketChannel ch) throws Exception {
                            ChannelPipeline pipeline = ch.pipeline();
                            if (sslContext != null) {
                                pipeline.addLast(sslContext.newHandler(ch.alloc()));
                            }
                            //添加一个HTTP的编解码器
                            pipeline.addLast(new HttpServerCodec());
                            //添加HTTP消息聚合器
                            pipeline.addLast(new HttpObjectAggregator(64 * 1024));
                            //添加一个自定义服务端Handler
                            pipeline.addLast(new HttpHelloWorldServerHandler());
                        }
                    });
            ChannelFuture future = bootstrap.bind(PORT).sync();
            System.err.println("Open your web browser and navigate to " +
                    (SSL? "https" : "http") + "://127.0.0.1:" + PORT + '/');

            future.channel().closeFuture().sync();
        } finally {
            boss.shutdownGracefully().sync();
            worker.shutdownGracefully().sync();
        }

    }

}

final SslContext sslContext;
      if (SSL) {
          SelfSignedCertificate certificate = new SelfSignedCertificate();
          sslContext = SslContextBuilder.forServer(certificate.certificate(), certificate.privateKey()).build();
      } else {
          sslContext = null;
      }

public class HttpHelloWorldServerHandler extends SimpleChannelInboundHandler<HttpObject> {
    private static final AsciiString CONTENT_TYPE = AsciiString.cached("Content-Type");
    private static final AsciiString CONTENT_LENGTH = AsciiString.cached("Content-Length");
    private static final AsciiString CONNECTION = AsciiString.cached("Connection");
    private static final AsciiString KEEP_ALIVE = AsciiString.cached("keep-alive");
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
        if (msg instanceof HttpRequest) {
            HttpRequest req = (HttpRequest) msg;
            System.out.println("浏览器请求方式："+req.method().name());
            String content = "";
            if ("/hello".equals(req.uri())) {
                content = "hello world";
                response2Client(ctx,req,content);
            } else {
                content = "Connect the Server";
                response2Client(ctx,req,content);
            }
        }
    }

    private void response2Client(ChannelHandlerContext ctx, HttpRequest req, String content) {
        boolean keepAlive = HttpUtil.isKeepAlive(req);
        FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, Unpooled.wrappedBuffer(content.getBytes()));
        response.headers().set(CONTENT_TYPE, "text/plain");
        response.headers().setInt(CONTENT_LENGTH, response.content().readableBytes());
        if (!keepAlive) {
            ctx.write(response).addListener(ChannelFutureListener.CLOSE);
        } else {
            response.headers().set(CONNECTION, KEEP_ALIVE);
            ctx.write(response);
        }
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

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