Netty学习(三)HelloWorld服务器

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Netty学习(三)HelloWorld服务器
例子来源于官网。
效果：
这里写图片描述

服务器初始化 HttpHelloWorldServerInitializer


package cn.pangpython.mynetty;import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.HttpServerExpectContinueHandler;
import io.netty.handler.ssl.SslContext;/*** 服务器初始化*/
public class HttpHelloWorldServerInitializer extends ChannelInitializer<SocketChannel> {private final SslContext sslCtx;public HttpHelloWorldServerInitializer(SslContext sslCtx) {this.sslCtx = sslCtx;}@Overridepublic void initChannel(SocketChannel ch) {ChannelPipeline p = ch.pipeline();if (sslCtx != null) {p.addLast(sslCtx.newHandler(ch.alloc()));}p.addLast(new HttpServerCodec());p.addLast(new HttpServerExpectContinueHandler());p.addLast(new HttpHelloWorldServerHandler());}
}

处理类 HttpHelloWorldServerHandler


package cn.pangpython.mynetty;import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFutureListener;
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.HttpRequest;
import io.netty.handler.codec.http.HttpUtil;
import io.netty.util.AsciiString;import static io.netty.handler.codec.http.HttpResponseStatus.OK;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;/*** 处理类*/
public class HttpHelloWorldServerHandler extends ChannelInboundHandlerAdapter {private static final byte[] CONTENT = { 'H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd' };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");@Overridepublic void channelReadComplete(ChannelHandlerContext ctx) {ctx.flush();}@Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) {if (msg instanceof HttpRequest) {HttpRequest req = (HttpRequest) msg;boolean keepAlive = HttpUtil.isKeepAlive(req);FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK, Unpooled.wrappedBuffer(CONTENT));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);}}}@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {cause.printStackTrace();ctx.close();}
}

主类 Main

package cn.pangpython.mynetty;import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.SslContextBuilder;
import io.netty.handler.ssl.util.SelfSignedCertificate;import javax.net.ssl.SSLException;
import java.security.cert.CertificateException;public class Main {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 InterruptedException, CertificateException, SSLException {// Configure SSL.final SslContext sslCtx;if (SSL) {SelfSignedCertificate ssc = new SelfSignedCertificate();sslCtx = SslContextBuilder.forServer(ssc.certificate(), ssc.privateKey()).build();} else {sslCtx = null;}// Configure the server.EventLoopGroup bossGroup = new NioEventLoopGroup(1);EventLoopGroup workerGroup = new NioEventLoopGroup();try {ServerBootstrap b = new ServerBootstrap();b.option(ChannelOption.SO_BACKLOG, 1024);b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class).handler(new LoggingHandler(LogLevel.INFO)).childHandler(new HttpHelloWorldServerInitializer(sslCtx));Channel ch = b.bind(PORT).sync().channel();System.err.println("Open your web browser and navigate to " +(SSL? "https" : "http") + "://127.0.0.1:" + PORT + '/');ch.closeFuture().sync();} finally {bossGroup.shutdownGracefully();workerGroup.shutdownGracefully();}}
}