Netty学习笔记 4.5 快速入门实例-HTTP服务
实例要求:使用IDEA 创建Netty项目
Netty 服务器在 6668 端口监听,浏览器发出请求 "http://localhost:6668/ "
服务器可以回复消息给客户端 "Hello! 我是服务器 5 " , 并对特定请求资源进行过滤.
目的:Netty 可以做Http服务开发,并且理解Handler实例和客户端及其请求的关系.
TestServer
package com.my.netty.http;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
public class TestServer {
public static void main(String[] args) throws Exception {
EventLoopGroup bossGroup = new NioEventLoopGroup(1);
EventLoopGroup workerGroup = new NioEventLoopGroup();
try {
ServerBootstrap serverBootstrap = new ServerBootstrap();
serverBootstrap.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class).childHandler(new TestServerInitializer());
ChannelFuture channelFuture = serverBootstrap.bind(6668).sync();
channelFuture.channel().closeFuture().sync();
}finally {
bossGroup.shutdownGracefully();
workerGroup.shutdownGracefully();
}
}
}
TestServerInitializer
package com.my.netty.http;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.http.HttpServerCodec;
public class TestServerInitializer extends ChannelInitializer<SocketChannel> {
@Override
protected void initChannel(SocketChannel ch) throws Exception {
//向管道加入处理器
//得到管道
ChannelPipeline pipeline = ch.pipeline();
//加入一个netty 提供的httpServerCodec codec =>[coder - decoder]
//HttpServerCodec 说明
//1. HttpServerCodec 是netty 提供的处理http的 编-解码器
pipeline.addLast("MyHttpServerCodec",new HttpServerCodec());
//2. 增加一个自定义的handler
pipeline.addLast("MyTestHttpServerHandler", new TestHttpServerHandler());
System.out.println("ok~~~~");
}
}
TestHttpServerHandler
package com.my.netty.http;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;
import java.net.URI;
/*
说明
1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter
2. HttpObject 客户端和服务器端相互通讯的数据被封装成 HttpObject
*/
public class TestHttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {
//channelRead0 读取客户端数据
@Override
protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
System.out.println("对应的channel=" + ctx.channel() + " pipeline=" + ctx
.pipeline() + " 通过pipeline获取channel" + ctx.pipeline().channel());
System.out.println("当前ctx的handler=" + ctx.handler());
//判断 msg 是不是 httprequest请求
if(msg instanceof HttpRequest) {
System.out.println("ctx 类型="+ctx.getClass());
System.out.println("pipeline hashcode" + ctx.pipeline().hashCode() + " TestHttpServerHandler hash=" + this.hashCode());
System.out.println("msg 类型=" + msg.getClass());
System.out.println("客户端地址" + ctx.channel().remoteAddress());
//获取到
HttpRequest httpRequest = (HttpRequest) msg;
//获取uri, 过滤指定的资源
URI uri = new URI(httpRequest.uri());
if("/favicon.ico".equals(uri.getPath())) {
System.out.println("请求了 favicon.ico, 不做响应");
return;
}
//回复信息给浏览器 [http协议]
ByteBuf content = Unpooled.copiedBuffer("hello, 我是服务器", CharsetUtil.UTF_8);
//构造一个http的相应,即 httpresponse
FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain");
response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());
//将构建好 response返回
ctx.writeAndFlush(response);
}
}
}