EventLoopGroup
parentGroup
=
new
NioEventLoopGroup
();
EventLoopGroup
childGroup
=
new
NioEventLoopGroup
();
try
{
ServerBootstrap
serverBootstrap
=
new
ServerBootstrap
();
serverBootstrap.group(parentGroup, childGroup)
.channel(NioServerSocketChannel.class).childHandler(
new
ChannelInit
());
ChannelFuture
channelFuture
=
serverBootstrap.bind(
8082
).sync();
channelFuture.channel().closeFuture().sync();
}
catch
(Exception e){
e.printStackTrace();
}
finally
{
parentGroup.shutdownGracefully();
childGroup.shutdownGracefully();
2、通道初始化
ChannelInitializer
特殊的通道处理器，提供一种简单的方法，对注册到EventLoop的通道进行初始化；比如此处设置的编码解码器，自定义处理器；
public class ChannelInit extends ChannelInitializer<SocketChannel> {
@Override
protected void initChannel(SocketChannel socketChannel) {
ChannelPipeline pipeline = socketChannel.pipeline();
pipeline.addLast("DefHttpServerCodec",new HttpServerCodec());
pipeline.addLast("DefHttpHandler", new DefHandler());
3、自定义处理器
处理对服务器端发起的访问，通常包括请求解析，具体的逻辑执行，请求响应等过程；
public class DefHandler extends SimpleChannelInboundHandler<HttpObject> {
@Override
protected void channelRead0(ChannelHandlerContext ctx, HttpObject message) throws Exception {
if(message instanceof HttpRequest) {
HttpRequest httpRequest = (HttpRequest) message;
String uri = httpRequest.uri();
String method = httpRequest.method().name();
log.info("【HttpRequest-URI:"+uri+"】");
log.info("【HttpRequest-method:"+method+"】");
Iterator<Map.Entry<String,String>> iterator = httpRequest.headers().iteratorAsString();
while (iterator.hasNext()){
Map.Entry<String,String> entry = iterator.next();
log.info("【Header-Key:"+entry.getKey()+";Header-Value:"+entry.getValue()+"】");
ByteBuf content = Unpooled.copiedBuffer("Netty服务", CharsetUtil.UTF_8);
FullHttpResponse response = new DefaultFullHttpResponse
(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain;charset=utf-8");
response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());
ctx.writeAndFlush(response);
4、测试请求
上面入门案例中，简单的配置了一个Netty服务器端，启动之后在浏览器中模拟访问即可；
http://127.0.0.1:8082/?id=1&name=Spring
三、Gateway集成
1、依赖层级
项目中Gateway网关依赖的版本为2.2.5.RELEASE，发现Netty依赖的版本为4.1.45.Final，是当下比较主流的版本；
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
<version>2.2.5.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
<version>2.3.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-reactor-netty</artifactId>
<version>2.3.2.RELEASE</version>
</dependency>
2、自动化配置
在Gateway网关的自动化配置配置类中，提供了Netty配置的管理；
@AutoConfigureBefore({ HttpHandlerAutoConfiguration.class,WebFluxAutoConfiguration.class })
@ConditionalOnClass(DispatcherHandler.class)
public class GatewayAutoConfiguration {
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(HttpClient.class)
protected static class NettyConfiguration {
@Bean
@ConditionalOnProperty(name = "spring.cloud.gateway.httpserver.wiretap")
public NettyWebServerFactoryCustomizer nettyServerWiretapCustomizer(
Environment environment, ServerProperties serverProperties) {
return new NettyWebServerFactoryCustomizer(environment, serverProperties) {
@Override
public void customize(NettyReactiveWebServerFactory factory) {
factory.addServerCustomizers(httpServer -> httpServer.wiretap(true));
super.customize(factory);
四、配置加载
1、基础配置
在工程的配置文件中，简单做一些基础性的设置；
server:
port: 8081
netty:
connection-timeout: 3000
2、属性配置类
在ServerProperties类中，并没有提供很多显式的Netty配置参数，更多信息需要参考工厂类；
@ConfigurationProperties(prefix = "server", ignoreUnknownFields = true)
public class ServerProperties {
private Integer port;
public static class Netty {
private Duration connectionTimeout;
3、配置加载分析
基于配置的属性，定制化管理Netty服务的信息；
public class NettyWebServerFactoryCustomizer
implements WebServerFactoryCustomizer<NettyReactiveWebServerFactory>{
private final Environment environment;
private final ServerProperties serverProperties;
@Override
public void customize(NettyReactiveWebServerFactory factory) {
PropertyMapper propertyMapper = PropertyMapper.get().alwaysApplyingWhenNonNull();
ServerProperties.Netty nettyProperties = this.serverProperties.getNetty();
propertyMapper.from(nettyProperties::getConnectionTimeout).whenNonNull()
.to((connectionTimeout) -> customizeConnectionTimeout(factory, connectionTimeout));
NettyReactiveWeb服务工厂，基于上述入门案例，创建WebServer时，部分参数信息出自LoopResources接口；
public class NettyReactiveWebServerFactory extends AbstractReactiveWebServerFactory {
private ReactorResourceFactory resourceFactory;
@Override
public WebServer getWebServer(HttpHandler httpHandler) {
HttpServer httpServer = createHttpServer();
ReactorHttpHandlerAdapter handlerAdapter = new ReactorHttpHandlerAdapter(httpHandler);
NettyWebServer webServer = new NettyWebServer(httpServer, handlerAdapter, this.lifecycleTimeout);
webServer.setRouteProviders(this.routeProviders);
return webServer;
private HttpServer createHttpServer() {
HttpServer server = HttpServer.create();
if (this.resourceFactory != null) {
LoopResources resources = this.resourceFactory.getLoopResources();
server = server.tcpConfiguration(
(tcpServer) -> tcpServer.runOn(resources).addressSupplier(this::getListenAddress));
return applyCustomizers(server);
五、周期管理方法
1、控制类
Gateway项目中，Netty服务核心控制类，通过NettyReactiveWebServerFactory工厂类创建，对Netty生命周期的管理提供了一层包装；
public class NettyWebServer implements WebServer {
private final HttpServer httpServer;
private final ReactorHttpHandlerAdapter handlerAdapter;
* 启动方法
@Override
public void start() throws WebServerException {
if (this.disposableServer == null) {
this.disposableServer = startHttpServer();
logger.info("Netty started on port(s): " + getPort());
startDaemonAwaitThread(this.disposableServer);
private DisposableServer startHttpServer() {
HttpServer server = this.httpServer;
if (this.routeProviders.isEmpty()) {
server = server.handle(this.handlerAdapter);
return server.bindNow();
* 停止方法
@Override
public void stop() throws WebServerException {
if (this.disposableServer != null) {
if (this.lifecycleTimeout != null) {
this
.disposableServer.disposeNow(this.lifecycleTimeout);
else {
this.disposableServer.disposeNow();
this.disposableServer = null;
2、管理类
Netty组件中抽象管理类，以安全的方式构建Http服务；
public abstract class HttpServer {
public static HttpServer create() {
return HttpServerBind.INSTANCE;
public final DisposableServer bindNow() {
return bindNow(Duration.ofSeconds(45));
public final HttpServer handle(BiFunction<? super HttpServerRequest, ? super
HttpServerResponse, ? extends Publisher<Void>> handler) {
return new HttpServerHandle(this, handler);
六、参考源码
编程文档：
https://gitee.com/cicadasmile/butte-java-note
应用仓库：
https://gitee.com/cicadasmile/butte-flyer-parent
