netty 实现tomcat的示例代码

public abstract class TomcatServlet {     public void service(ServletRequest request, ServletResponse response){        if ("GET".equalsIgnoreCase(request.getMethod())){            doGet(request, response);        }else if ("POST".equalsIgnoreCase(request.getMethod())){            doPost(request, response);        }else {            doResponse(response, "暂不支持其它请求方法");        }    }     public abstract void doGet(ServletRequest request, ServletResponse response);    public abstract void doPost(ServletRequest request, ServletResponse response);     public void doResponse(ServletResponse response, String message){        response.write(message);    }}          

@Datapublic class ServletRequest {     private ChannelHandlerContext context;    private HttpRequest httpRequest;     public ServletRequest(){     }     public ServletRequest(ChannelHandlerContext context, HttpRequest httpRequest){        this.context = context;        this.httpRequest = httpRequest;    }     public String getMethod(){        return httpRequest.method().name();    }     public HttpHeaders getHeaders(){        return httpRequest.headers();    }     public Map<String, List<String>> getParameters(){        QueryStringDecoder decoder = new QueryStringDecoder(httpRequest.uri());        return decoder.parameters();    }     public Map<String,String> getPostFormParameters(){        Map<String,String> params = new HashMap<>();         HttpPostRequestDecoder decoder = new HttpPostRequestDecoder(httpRequest);        decoder.getBodyHttpDatas().forEach(item -> {            if (item.getHttpDataType() == InterfaceHttpData.HttpDataType.Attribute){                Attribute attribute = (Attribute) item;                 try {                    String key = attribute.getName();                    String value = attribute.getValue();                     params.put(key, value);                }catch (Exception e){                    e.printStackTrace();                }            }        });         return params;    }     public Map<String, Object> getPostBody(){        ByteBuf content = ((FullHttpRequest)httpRequest).content();        byte[] bytes = new byte[content.readableBytes()];        content.readBytes(bytes);         return JSON.parseObject(new String(bytes)).getInnerMap();    }}

@Datapublic class ServletResponse {     private ChannelHandlerContext context;    private HttpRequest httpRequest;     public ServletResponse(){     }     public ServletResponse(ChannelHandlerContext context, HttpRequest httpRequest){        this.context = context;        this.httpRequest = httpRequest;    }     public void write(String message){        FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);        response.headers().set("Content-Type","application/json;charset=utf-8");        response.content().writeCharSequence(message, StandardCharsets.UTF_8);         context.channel().writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);    }}

ublic class CustomServlet extends TomcatServlet{     @Override    public void doGet(ServletRequest request, ServletResponse response) {        System.out.println("处理GET请求");        System.out.println("请求参数为：");        request.getParameters().forEach((key,value) -> System.out.println(key + " ==> "+value));         doResponse(response, "GET success");    }     @Override    public void doPost(ServletRequest request, ServletResponse response) {        if (request.getHeaders().get("Content-Type").contains("x-www-form-urlencoded")){            System.out.println("处理POST Form请求");            System.out.println("请求参数为：");            request.getPostFormParameters().forEach((key,value) -> System.out.println(key + " ==> " + value));             doResponse(response, "POST Form success");        }else if (request.getHeaders().get("Content-Type").contains("application/json")){            System.out.println("处理POST json请求");            System.out.println("请求参数为：");            request.getPostBody().forEach((key,value) -> System.out.println(key + " ==> " + value));             doResponse(response, "POST json success");        }else {            doResponse(response, "error：暂不支持其它post请求方式");        }    }}

public class ServletMapping {     private static final Map<String,TomcatServlet> urlServletMapping = new HashMap<>();     public static Map<String, TomcatServlet> getUrlServletMapping(){        return urlServletMapping;    }}

servlet.url=/helloservlet.className=com.example.demo.tomcat.servlet.CustomServlet

public class CustomServerHandler extends SimpleChannelInboundHandler<FullHttpRequest> {     @Override    protected void channelRead0(ChannelHandlerContext channelHandlerContext, FullHttpRequest request) throws Exception {        String uri = request.uri();        String path = uri;        if (uri.contains("?")){            path = uri.substring(0,uri.indexOf("?"));        }         if (ServletMapping.getUrlServletMapping().containsKey(path)){            ServletRequest servletRequest = new ServletRequest(channelHandlerContext, request);            ServletResponse servletResponse = new ServletResponse(channelHandlerContext, request);             ServletMapping.getUrlServletMapping().get(path).service(servletRequest, servletResponse);        }else {            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);            response.content().writeCharSequence("404 NOT FOUND："+path+"不存在", StandardCharsets.UTF_8);             channelHandlerContext.channel().writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);        }    }}

public class NettyServer {     private static final Properties webProperties = new Properties();     public static void init(){        try {            InputStream inputStream = new FileInputStream("./web.properties");            webProperties.load(inputStream);             for (Object item : webProperties.keySet()){                String key = (String)item;                if (key.endsWith(".url")){                    String servletKey = key.replaceAll("//.url","//.className");                    String servletName = webProperties.getProperty(servletKey);                     TomcatServlet servlet = (TomcatServlet) Class.forName(servletName).newInstance();                    ServletMapping.getUrlServletMapping().put(webProperties.getProperty(key),servlet);                }            }        }catch (Exception e){            e.printStackTrace();        }    }     public static void startServer(int port){        init();         EventLoopGroup bossGroup = new NioEventLoopGroup();        EventLoopGroup workerGroup = new NioEventLoopGroup();         try {            ServerBootstrap serverBootstrap = new ServerBootstrap();            serverBootstrap.group(bossGroup, workerGroup)                    .channel(NioServerSocketChannel.class)                    .option(ChannelOption.SO_BACKLOG, 128)                    .childOption(ChannelOption.SO_KEEPALIVE, true)                    .childHandler(new ChannelInitializer<SocketChannel>() {                         @Override                        protected void initChannel(SocketChannel socketChannel) throws Exception {                            ChannelPipeline channelPipeline = socketChannel.pipeline();                            channelPipeline.addLast(new HttpRequestDecoder());                            channelPipeline.addLast(new HttpResponseEncoder());                            channelPipeline.addLast(new HttpObjectAggregator(65535));                            channelPipeline.addLast(new CustomServerHandler());                        }                    });             ChannelFuture channelFuture = serverBootstrap.bind(port).sync();            channelFuture.channel().closeFuture().sync();        }catch (Exception e){            e.printStackTrace();        }finally {            bossGroup.shutdownGracefully();            workerGroup.shutdownGracefully();        }    }     public static void main(String[] args) {        startServer(8000);    }}